U.S. patent application number 16/019523 was filed with the patent office on 2018-10-25 for methods and devices for evaluating the contents of materials.
The applicant listed for this patent is Michael Smith. Invention is credited to Michael Smith.
Application Number | 20180306031 16/019523 |
Document ID | / |
Family ID | 62559249 |
Filed Date | 2018-10-25 |
United States Patent
Application |
20180306031 |
Kind Code |
A1 |
Smith; Michael |
October 25, 2018 |
METHODS AND DEVICES FOR EVALUATING THE CONTENTS OF MATERIALS
Abstract
Methods for determining the hardness and/or ductility of a
material by compression of the material are provided as a first
aspect of the invention. Typically, compression is performed on
multiple sides of a geologic material sample in a contemporaneous
manner. Devices and systems for performing such methods also are
provided. These methods, devices, and systems can be combined with
additional methods, devices, and systems of the invention that
provide for the analysis of compounds contained in such samples,
which can indicate the presence of valuable materials, such as
petroleum-associated hydrocarbons. Alternatively, these additional
methods, devices, and systems can also stand independently of the
methods, devices, and systems for analyzing ductility and/or
hardness of materials.
Inventors: |
Smith; Michael; (Tulsa,
OK) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Smith; Michael |
Tulsa |
OK |
US |
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|
Family ID: |
62559249 |
Appl. No.: |
16/019523 |
Filed: |
June 26, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/US17/65921 |
Dec 12, 2017 |
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16019523 |
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62434399 |
Dec 14, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01M 3/202 20130101;
G01N 3/40 20130101; G01N 3/12 20130101; H01J 49/00 20130101; B27K
5/0005 20130101; B29B 17/0408 20130101; E21B 49/081 20130101; G01N
3/08 20130101; E21B 49/005 20130101; H01J 49/26 20130101; E21B
43/26 20130101; E21B 49/02 20130101; G01N 1/286 20130101; H01J
49/0409 20130101; H01J 49/0468 20130101; G01N 33/241 20130101; G01N
33/6848 20130101; E21B 49/08 20130101; G01N 1/24 20130101; H01J
49/0422 20130101; G01N 1/4022 20130101; G01N 2015/1043 20130101;
G01N 2001/4033 20130101 |
International
Class: |
E21B 49/00 20060101
E21B049/00; E21B 49/02 20060101 E21B049/02; G01N 1/24 20060101
G01N001/24; G01N 3/12 20060101 G01N003/12; G01N 3/40 20060101
G01N003/40 |
Claims
1. A method for analyzing volatile substances in a material
comprising (a) applying one or more forces to a sample of a
material causing the release of a first gas from the material
containing an analyzable amount of one or more volatile substances,
(b) trapping and concentrating the first gas in or with a trapping
media in an analyzable amount to generate an aliquot, (c) isolating
the aliquot from the sample, (d) releasing volatile substances from
the aliquot as released gasses in a predictable sequence, (e)
analyzing the volatile substance chemistry of at least one of the
released gasses to obtain an analysis of the volatile substances in
the aliquot.
2. The method of claim 1, wherein the step of trapping and
concentrating the first gas comprises cryogenically capturing the
gas on a cryogenic trap.
3. The method of claim 2, wherein the analysis of each aliquot
comprises subjecting one or more volatile substances released from
the aliquot to mass spectrometry.
4. The method of claim 3, wherein the method comprises collecting a
portion of the first gas that will not bind to the trapping media
as a separate non-condensable gas, separating the non-condensable
gas from the first gas, and subjecting the non-condensable gas to
mass spectrometry analysis.
5. The method of claim 4, wherein the one or more forces comprises
exposing the sample to a vacuum at a maximum negative pressure of
1.times.10.sup.-2 millibars.
6. The method of claim 5, wherein the analyses provide information
concerning the quantity of one or more volatile compounds in the
material.
7. The method of claim 6, wherein the method comprises analyzing at
least about 75% of the total volatile substances contained in the
sample.
8. The method of claim 8, wherein the sample is contained in a
container capable of retaining the first gas when released from the
sample and the method comprises selectively allowing the first gas
to exit the container and come in contact with the media.
9. The method of claim 8, wherein the method further comprises
mechanically disrupting the sample in the container in a manner
such that no volatile substances are released from the container
prior to allowing the first gas to come in contact with the
trapping media.
10. The method of claim 9, wherein the container comprises a
portion that is designed to promote mechanical disruption of the
sample without loss of volatile substances.
11. The method of claim 10, wherein the volatile substances
released by the material comprise one or more C1-C20
hydrocarbons.
12. The method of claim 11, wherein the material is a naturally
occurring geologic formation and the sample is taken from the
formation.
13. The method of claim 12, wherein the amount of the one or more
volatile compounds in the material is predictive of the amount of
oil, natural gas, or both present in the material.
14. The method of claim 13, wherein the sample is a petroleum
drilling cutting.
15. The method of claim 3, wherein the method comprises repeating
the steps of the method for one or more additional cycles, wherein
in each additional cycle the one or more forces cause the release
of an additional gas having a volatile substance content that is
different from the first gas and each other additional gas.
16. The method of claim 15, wherein applying one or more forces on
the sample comprises exposing the sample to at least two different
pressures, the first pressure causing the release of the first gas
and the second pressure causing the release of a second gas having
a volatile composition profile that is different from the first
gas, wherein the method comprises separately trapping the first gas
and second gas on the media so as to form first and second aliquots
and separately analyzing the first and second aliquots by mass
spectrometry.
17. The method of claim 16, wherein the method further comprises
evaluating the permeability of the sample by assessing differences
in volatile substances released from two or more aliquots obtained
by extraction of the volatile substances under at least two
different sets of conditions that each result in a distinct set of
released gasses.
18. The method of claim 17, wherein the method further comprises
removing potentially interfering gasses from contact with the media
prior to analyzing gasses released from each aliquot.
19. The method of claim 3, wherein the method is performed with two
or more samples taken from different portions of a geologic
formation and the results of the analyses of each of the released
gasses correlates to the amount of petroleum in the portions of the
geologic formation.
20. The method of claim 15, wherein the method is performed with
two or more samples taken from different portions of a geologic
formation and the results of the analyses of each of the released
gasses correlates to the amount of petroleum in the portions of the
geologic formation.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of PCT/US2017/065921,
filed Dec. 12, 2017 entitled Methods and Devices for Evaluation the
Contents of Materials which claims the benefit of U.S. Provisional
Application No. 62/434,399, filed Dec. 14, 2016, entitled Methods
and Devices for Evaluating the Contents of Materials, the entirety
of each of which being hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention pertains to novel methods of evaluating the
contents of materials, including, for example, volatile substances
such as petroleum-related hydrocarbons in geological materials, as
well as devices that can be used in the practice of the methods and
other applications.
BACKGROUND OF THE INVENTION
[0003] Human evaluation of the content of materials has probably
been practiced for longer than any written records. However, the
ability to use information associated with a material to understand
the properties of associated materials, such as surrounding
geologic formations, has been largely developed in the last 100
years, beginning with the Schlumberger brothers' discovery that
electric resistivity could be used to evaluate the structure and
likely content of geologic structures, and thus provide a mechanism
for finding subsurface materials, such as fossil fuel deposits.
While a significant advance, resistivity has proven to be of
limited utility, especially in modern times in which easy to find
petroleum and natural gas deposits are increasingly more difficult
to detect with such technology.
[0004] Prior technology involving the analysis of rock materials,
such as to determine the presence of hydrocarbons in a geologic
formation, have focused on the analysis of material in fluid
inclusions. Fluid inclusions are often characterized as "bubbles"
of fluid trapped within a host material, such as rock. These
compartments within rock or other material are usually very small,
from 1 to 20 microns across. Fluid inclusions are characterized by
being completely sealed and isolated from the environment,
typically over very long period of time (on a geologic scale--e.g.,
over millions of years). The contents of fluid inclusions are
believed to be the remnants of the exact fluid associated with the
rock material at formation. As such, the content of inclusions can
provide information about the fluid composition, temperature and
pressure at which a material was formed and what it may
contain.
[0005] In one type of typical fluid inclusion analyses, a rock
sample, usually from a sedimentary rock, is crushed under strong
vacuum and the trapped fluids that are released from the crushing
are analyzed, such as with a mass spectrometer. Prior to my
inventions described herein, the conditions under which mass
spectrometers operate have dictated how the devices and methods for
fluid inclusion analysis have been performed. Fluid inclusion
materials have shown some usefulness in the discovery of
hydrocarbon materials and today is a commonly practiced method
performed on materials obtained from oil well drilling. However,
fluid inclusion analysis also is of limited utility due to a number
of issues, such as the content of the inclusion often not matching
the present-day fluids in the geologic formation.
[0006] Specific patents describing my prior inventions, the
inventions of my co-inventors, and other inventors include U.S.
Pat. No. 4,960,567, which relates to a method for obtaining gasses
from fluid inclusions for analysis through mass spectrometry and
U.S. Pat. No. 5,241,859, which describes a method in which material
from a collection of fluid inclusions are analyzed to identify
collections that are rich in hydrocarbons, which can then be
further analyzed, such as through mass spectrometry analysis. U.S.
Pat. No. 5,328,849 describes methods for mapping subsurface
formations by analyzing fluid inclusions in several samples through
specialized devices I also invented.
[0007] U.S. Pat. No. 6,661,000 describes an invention made by me
and my co-inventors wherein we invented a method for analyzing
surface and pore liquids, as opposed to fluid inclusions, by a
method in which cuttings or other samples are subjected directly to
mass spectrometry analysis under high vacuum. However, one of the
shortcomings with that method is the loss of gasses associated with
the sample due to the need to apply such relatively high vacuum
levels in order to make the devices we invented operate.
[0008] The invention provides methods and devices that not only
address the limitations of these prior inventions but also greatly
expand on them in terms of the applicability of methods to various
materials and associated materials, extending well beyond simple
analysis of potential hydrocarbon-associated rock samples. These
and other advantages of the invention, as well as additional
inventive features, will be apparent from the description of the
invention provided herein.
SUMMARY OF THE INVENTION
[0009] In a first aspect, the invention provides new methods for
determining the ability to subject a geologic material to fracking
and similar processes in which the hardness and/or ductility of a
material is determined by compression of one or more samples of the
material, especially on multiple sides of the sample in a
contemporaneous manner. The sample is typically associated with a
drill operation and often is a cutting. The methods typically
comprise analysis of many samples, such as 5, 10, 15, 20, 30, 40,
50, or more samples (e.g., 100, 250, 500, 750, 1,000, 1,250, 1,500,
or more samples), usually from different locations with respect to
most of the other analyzed samples (such as being separated by at
least 0.75 vertical and/or horizontal feet). The invention further
provides devices and systems for performing such methods of the
first aspect.
[0010] These methods, devices, and systems can be combined with
additional methods, devices, and systems of the invention that
provide for the analysis of volatile substances contained in such
samples, such as cuttings, which can indicate the presence of
substances in the material associated with the sample, such as
petroleum-associated hydrocarbons (oil and/or gas). Alternatively,
such additional methods, devices, and systems can also stand
independently of the methods, devices, and systems for analyzing
ductility and/or hardness of materials of the first aspect of the
invention, as a second, independent aspect of the invention. The
method of the second aspect typically comprises exposing the
samples to one or more forces that allow or promote the release of
the volatile substances, capturing the volatile substances, and
then analyzing the volatile substances, so as to identify the
nature of the composition of the material. Such methods often
comprise application of a gentle force, such as a gentle vacuum
step (e.g., at about 10-about 100 millibars), which allows for
capture of volatile fluids in the sample without significant loss
of such materials in the analytical method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a representation of an illustrative device/system
of the invention for analyzing both the compressibility of samples
and the volatile substance content of such samples through a
non-selective trap of condensable gasses, a separate trap of
non-condensable gasses, and mass spectrometry analysis of such
compounds.
[0012] FIG. 2 is an example of a data set obtained by performing
methods of the invention in connection with petroleum
well-associated cuttings.
[0013] FIG. 3 provides another example of a data set obtained by
performing methods of the invention in connection with petroleum
well-associated cuttings.
[0014] FIG. 3B provides a simplified, stylized view of select data
shown in FIG. 3.
[0015] FIGS. 4A is an illustrative plot of oil, water, and oil
saturated water in connection with a vertically oriented petroleum
well.
[0016] FIG. 4B is a simplified representation of key data provided
in FIG. 4A.
[0017] FIG. 5 provides yet another example of data obtained by
performing methods of the invention on cuttings.
[0018] FIG. 5B provides a simplified representation of select data
presented in FIG. 5.
[0019] FIG. 6 is a representation of a type of petroleum-associated
geologic formation that can be identified and characterized by use
of methods of the invention.
[0020] FIG. 7 provides a plot of acetic acid measurements in a
geologic formation against resistivity log data to identify
petroleum associated regions in sandstone formations/sands.
[0021] FIG. 8A and 8B provide a plot of multiple hydrocarbons at
different depths to analyze the nature of petroleum deposits in a
geologic formation.
[0022] FIG. 8C provides a stylized representation of data
associated with a particular type of geologic deposit that can be
characterized by methods of the invention.
[0023] FIG. 9 is an illustrative representation of mapping a region
of sites using the method of the invention to characterize a larger
area comprising multiple drilling sites.
[0024] FIG. 10 is another plot of data obtained using methods of
the invention including hydrocarbon data, oil saturated water, and
other data elements used to identify and characterize deposits
within a geologic formation at different depths.
[0025] FIG. 10A is a simplified representation of key data patterns
in FIG. 10.
[0026] FIG. 11 provides a representation of two data sets for
different formations/sites that can be differentially analyzed by
methods of the invention.
[0027] FIG. 12 provides an illustration of a well site device for
frackability/compression analysis of cuttings allowing for real
time/near real time steering of a lateral well.
DETAILED DESCRIPTION OF THE INVENTION
[0028] The invention described herein provides various types of
devices and methods for analyzing the contents of hard
mineral-based materials, such as rock samples taken from geologic
formations. One key use of these methods and devices is the
analysis of the drill cuttings from petroleum wells for the
contents of certain compounds in such cuttings or that can be
obtained from such cuttings, which in turn provide information
about the geologic material associated with the cuttings. However,
the methods and devices of the invention are not limited to such
applications and settings and can be applied to other settings, as
will be discussed further herein.
[0029] In a primary aspect, the invention described herein provides
a method for analyzing volatile substances in a material comprising
the steps of (a) providing an analyzable sample of a material
containing an analyzable amount of one or more volatile substances,
(b) permitting the release of fluid (e.g., gas) containing the
volatile substances from the material, (c) optionally subjecting
the sample to one or more forces to aid in the release of the
fluid, (e) optionally trapping the fluid by contact with a media,
in an analyzable amount (an aliquot), (d) optionally isolating the
fluid from the material, (e1) applying energy or one or more forces
to the aliquot so as to cause volatile compounds in the aliquot, if
present, to form other chemical substances (energy-treated
gas(ses)) in a predictable manner and/or (e2) releasing volatile
substances from the aliquot as trap-released fluids in a
predictable sequence, and (f) analyzing the chemistry of one or
more trap-released fluids and/or energy-treated fluids.
[0030] The inventive methods described herein can be practiced with
any suitable material containing any suitable number and/or
suitable number of any suitable type of volatile substances.
Suitability in this respect means that the volatile substances are
amenable to analysis by the methods and/or devices of the
invention, which can be determined by the principles described here
or through application of routine experimentation. A volatile
substance in the context of the invention is a material that will
take the form of a gas under the conditions in which the method is
performed. Conditions relevant to whether a material is in the form
of a gas at a particular time include the pressure the material is
under at the time. In one aspect of the invention, at least one
volatile substance is released from the material at atmospheric
pressure. In another aspect, at least one volatile material
analyzed by the method is released from the material under a vacuum
(a pressure lower than atmospheric pressure--i.e., a pressure of
less than about 760 Torr or 1.013.times.10.sup.5 Pa) or
significantly more of the material is released under a vacuum than
at atmospheric pressure (such as at least about 2 times, at least
about 3 times, at least about 5 times, at least about 10 times, at
least about 20 times, at least about 30 times, at least about 50
times, or at least about 100 times atmospheric pressure).
[0031] In a particular aspect, the method includes analyzing at
least one volatile substance that is released from the material
under low vacuum conditions. Low vacuum conditions mean pressure
conditions ranging from about 760 to about 25 Torr or
1.times.10.sup.5 to 3.times.10.sup.3 Pa (in this document each
disclosure of a quantity modified by modifiers such as "about" is
to be construed as simultaneously providing the corresponding exact
disclosure and each disclosure of a range is to be construed as
disclosing each unit of the same order of magnitude as the end
points of the range, e.g., a disclosure of the range of 1-5 also is
to be construed as disclosing the numbers 1, 2, 3, 4, and 5
individually). In another exemplary aspect, the method includes the
step of analyzing at least one volatile substance that is released
at under but close to 1000 millibars, such as about 40 millibars to
about 950 millibars, e.g., about 50 millibars to about 900
millibars, about 100 millibars to about 800 millibars, such as
about 150 millibars to about 750 millibars, or any combination of
such low and high-end points.
[0032] In another context, the method also or alternatively
includes analyzing at least one volatile substance that is released
from the material under medium vacuum conditions. Medium vacuum
conditions mean pressures of about 25 Torr to about
1.times.10.sup.-3 Torr (3.times.10.sup.3 to 1.times.10.sup.-1 Pa).
In another aspect, the method includes analyzing at least one
volatile substance that is released from the material under a
pressure of about 50 millibars (e.g., applying one more pressures
of about 20-80 millibars, such as about 30-70 millibars) and still
another aspect the method comprises performing an analysis on an
aliquot obtained by extraction at one or more pressures in the
range of about 30 millibars to about 10 millibars, such as about 25
millibars to about 12 millibars, e.g., about 20 millibars to about
15 millibars, or any other combination of such low and high end
points.
[0033] In another aspect, the invention also includes analyzing at
least one volatile substance that is released from the material
under high vacuum conditions. High vacuum conditions mean about
1.times.10.sup.-3 to about 1.times.10.sup.-9 Torr
(1.times.10.sup.-1 to 1.times.10.sup.-7 Pa). In another respect,
the invention includes analyzing at least one volatile substance
released under vacuum pressures of less than about 5 millibars,
such as less than about 2 millibars, such as less than 1 millibar.
For example, in another aspect, the invention comprises analyzing
at least one volatile substance released under vacuum pressures of
about 1.times.10.sup.-2 millibars or less, such as about
1.times.10.sup.-3 to about 1.times.10.sup.-9 millibars.
[0034] In still other aspects of the invention, the method does not
comprise application of high vacuum (such as those described
above), which in one respect distinguishes such aspects of this
invention from prior art methods which include or are dependent
upon the application of high vacuum to perform analysis of
materials. In still other aspects, the practice of the method of
the invention lacks application of either any high vacuum or any
medium vacuum in the release of volatile compounds. This
distinguishes these aspects, among other things, from prior art
methods, such as many forms of fluid inclusion analysis, which
typically require application of high vacuum and/or medium
vacuum.
[0035] The material also can be any material which can be suitably
subjected to the methods of the invention. In one typical context
the material is a geologic material, such as rock material, a mud,
or a soil, or a drilling byproduct, especially drilling mud or a
drill cutting. In the context of this invention terms such as
"cuttings" and "drill cuttings' means rock fragments that are
brought to the surface in a drilling operation (such terms are
generally understood in the art). Typically, drill cuttings are
rocks that are maintained separated from drill muds in a shaker
table operation or similar separation process. Drill cuttings can
have any suitable size. The size of cuttings produced at a well
will depend on several factors including the geologic material
being drilled through and the drill bit used, with more modern
drill bits often forming smaller cuttings. Particle sizes of
cuttings can be, for example, as small as about 5 microns (e.g.,
about 10 microns or larger, about 20 microns or larger, about 25
microns or larger, about 50 microns or larger, etc.), but typically
the cuttings will have particle sizes of at least about 100
microns, such as at least about 150 microns, or at least about 200
microns (e.g., about 250 microns or greater), and may be
significantly larger, such as up to about 7.5 mm (e.g., about 6.5
mm or less, about 6 mm or less, or about 5 mm or less). Commonly,
cuttings that typically have a particle size of between about 0.5
mm to about 1 mm and about 5 mm to about 6 mm are used in methods
of the invention. However, in a particularly unexpected aspect of
the invention (as exemplified elsewhere herein) the method has been
performed using very small cuttings that were produced in a coring
process, which are significantly smaller in size than typical
cuttings obtained in oil production or exploration. Thus, for
example, the method can be performed with cuttings of about 100
microns to about 5 mm, about 50 microns to about 10 mm, about 25
microns to about 7 mm, about 25 microns to about 12.5 mm, about 50
microns to about 6.5 mm, about 0.2 mm to about 6 mm, about 0.25 mm
to about 5 mm, or about 0.5 mm to about 5 mm. These are exemplary
ranges, and these endpoints of any one of these ranges can be
interchanged with end points of any other range to create other
suitable ranges in which to focus other exemplary methods of the
invention.
[0036] "Drilling mud", "muds", or "drilling fluid" in the context
of this invention refers to a material that is distinguished from
cuttings. Drilling mud is material that is at least initially
introduced to a well site and used by the operator of a drilling
operation to perform one or more functions including providing
hydrostatic pressure to prevent formation fluids from entering into
the well bore, maintaining the temperature and/or "cleanliness" of
the drill bit (or at least preventing overheating and/or
obstruction), maintaining the structural integrity of the bore
hole, and/or aiding in the carrying out of drill cuttings. Drilling
muds commonly will contain materials such as bentonite, barite, or
hematite and can be water-based or oil-based. Muds often are dense
materials and thixotropic, meaning that they become more fluid with
application of agitation. The nature of drilling muds and the
differences between drilling muds and cuttings will be understood
by those skilled in the art.
[0037] In a specific context, the material is rock or mud material
that is associated with either exploratory drilling or production
drilling for petroleum, natural gas, or related materials, however
materials obtained from other activities such as exploratory and
production drilling for economic mineral deposits and geothermal
energy also or alternatively could be used in practicing the
methods of the invention. The material also or alternatively can be
from other sources than from natural geologic formations or other
non-petroleum-related geologic samples, or even biological samples
such as teeth, bones, and the like (e.g., food or biomass from any
type of living organism whether viable or non-viable). In this
respect, the methods of the invention may have application in
various forensic and/or intelligence applications, for determining
the impact of processes on materials, the historical source or
modulation of materials, and/or, for example, the origin of
materials or other information about the nature of such materials.
For example, in another context the material is construction
material, such as material used in building of commercial
buildings, bridges, roads, construction sites, antiquities, and the
like. The methods also can be applied to other man-made materials
such as ceramics and other types of materials used in the
manufacture or construction of other devices and structures, such
as semiconductors.
[0038] In one aspect of the invention, the samples selected for
analysis in the performance of the method comprise, are
substantially comprised of (i.e., more than about 20% of the
samples are), are primarily comprised of (i.e., more than 51% of
the samples are), consist essentially of (are comprised of to a
level that the amount of non-conforming material does not impact
the nature of the total sample or sample set), or consist entirely
of, material that substantially lack relevant fluid inclusions
("RFIs"). "Relevant fluid inclusions" or "RFIs" in the context of
this invention refers to fluid inclusions that (1) contain one or
more materials that are indicative of the presence of a substance
in the material (at least in the inclusions), such as petroleum or
petroleum-related substances (e.g., organic acids, hydrocarbons,
and the like, such as acetic acid) and (2) the presence of such
materials reflect the present condition of the material (in terms
of the presence of the target substance). Samples may lack relevant
fluid inclusions for a number of reasons, such as relevant fluid
inclusions may have never formed in the material (e.g., shallow,
unconsolidated, young sandstone oil reservoirs in the Gulf of
Mexico) or the relevant fluid inclusions may have been destroyed by
natural and/or human processes (e.g., meteorite impact or drilling
with polycrystalline diamond compact ("PDC") drill bits). As
indicated elsewhere, often fluid inclusions will contain ancient
fluids that often do not reflect the present fluid content of the
material. In certain cases, relatively "young" fluid inclusions can
form in a material or older fluid inclusions may be filled by
relatively "young" material that is present in a material. Such
fluid inclusions can be classified as RFIs. Non-relevant fluid
inclusions ("NFIs") may still provide relevant information to
understanding the material, but they are less probative with
respect to the fluid content of the material than RFIs.
Substantially lacking RFIs means that less than 0.000005% of the
volume of the sample is made up of target substance (e.g.,
petroleum) or target substance-related fluid inclusions (e.g., only
about 0.05 ppm or less of the sample volume is made up of oil or an
oil-relevant substance). In some cases the invention is practiced
wherein the amount of RFIs is even less, such as 0.025 ppm or less,
about 0.02 ppm or less, or even about 0.01 ppm or less of the
volume of the sample is made up of target substance-containing or
target substance-relevant fluids (in even further aspects the
amount of RFIs in the sample is even less such as about 20 parts
per trillion of the volume of the sample or less, about 10 parts
per trillion of the volume of the sample or less, about 5 parts per
trillion of the volume of the sample or less, or even about 1 parts
per trillion of the volume of the sample or less. In still other
aspects, the sample or some of the sample(s) analyzed contain no
detectable amount of RFI. In some cases, the sample may contain
more volume of fluid inclusions, however the fluid inclusions will
be known to not be relevant in the sense that there is information
that informs the artisan that material in the fluid inclusion is
not indicative of the fluid content of the material (e.g., the
inclusion is indicative of the presence of oil, but it is known
from drilling that the content of the material reflects little to
no oil being present in the material). In certain aspects, the
material and/or the sample is or comprises a material that lacks
materials that will form a sufficient amount, size, or type of
inclusion to be relevant, such as many shales or
unconsolidated/young sands, which commonly lack material that is
hard enough to sufficiently form inclusions that can provide
detectable levels of RFIs even if the target substance is present
in the material. It is important to understand that the term
"target" in this and other contexts of describing aspects of the
invention can mean, but does not always mean, a specific substance
that is expected to be present or that is sought by the analytical
methods of the invention. Thus, for example, the "target" can be
one or more unknown materials that are in a material, such as one
or more substances that are included in drill cuttings or other
geologic material but that have no known composition prior to the
analysis.
[0039] In another aspect of the invention, the samples analyzed
and/or the material comprise a low number of RFIs. For example, in
a particular facet of the invention the sample is a collection of
cuttings in which less than about 20%, less than about 15%, or
about 10% or less, such as about 5% or less of the cuttings
comprise RFIs.
[0040] In other aspects, materials or samples with fluid inclusions
can be included intentionally and will be included commonly in the
sample and/or material, and, in such cases, the method optionally
can additionally comprise, as discussed below, performance of other
methods on materials containing fluid inclusions taken from site
and/or included in the samples.
[0041] The material and/or samples typically will include fissures,
fractures, pockets, cracks, etc., which contain target materials of
interest, such as volatile hydrocarbons. Such fissures, fractures,
etc. (referred collectively herein as "target substance pores" or
"TSPs"), will often desirably contain target substance or target
substance-relevant material (e.g., such as organic acids and/or
hydrocarbons that are indicative of the presence of petroleum) that
also in some cases are (1) present in relevant amounts in the
material (either in fluid form or are absorbed or adsorbed in the
material), rather than material that are artifacts of prior
existing conditions, as is the case with many NFIs, (2) are exposed
to the surrounding environment in some amount (such as by being
contained in a pore in the material that is exposed to the
surrounding environment) (in other words are not completely sealed
off from the environment as is the case with fluid inclusions), or
(3) can be characterized in satisfying both (1) and (2). A "pore
fluid" in the context of this invention means a substance that is
ordinarily liquid or gas in association with the material, contains
one or more volatiles, and is found in a TSP and satisfies
conditions (1), (2), or (3) of the preceding sentence. In some
aspects, the invention is characterized by analyzing one or more
samples containing an analyzable amount of pore fluid(s) and/or by
analyzing one or more samples containing an analyzable amount of a
pore fluid-related substance.
[0042] In a set of particular aspects, the material consists of,
comprises, or is substantially comprised of a geologic material
that has not experienced significant enough burial diagenesis to
have formed fluid inclusions. "Substantially comprised of in the
context of this invention means that a substantially majority, such
as at least 65%, more often at least 75%, such as at least 80%, at
least 85%, at least 90%, or even at least 95% of the referenced
material or composition is comprised of the component at issue. In
particular aspects, the material consists of, is comprised of, or
is substantially comprised of "young sands." In the context of this
invention a "young sand" means recent, Pliocene, and Miocene-age
sediments (e.g., 0-5 million years of age). For such sands that are
buried about 10,000 feet below surface level or less in a
tectonically quiet area (an area with relatively few earthquakes),
RFIs will typically not be present or will be substantially
lacking, as described elsewhere herein.
[0043] In yet another aspect, the sample and material comprise a
"tight carbonate" material. A "tight carbonate" in the context of
the inventive methods means a material that comprises a substantial
carbonate portion (e.g., at least about 90% of the material is
comprised of one or more carbonates), which exhibit low
permeability (e.g., about 15 millidarcies or less, about 10
millidarcies or less, or about 5 millidarcies or less). In one
aspect, the material is a material that is not suitable for
traditional Sw analysis, because electricity cannot sufficiently
flow through the material to give proper signals required for
traditional resistivity-based Sw analysis. The methods of the
invention also or alternatively can be applied to similar types of
materials from other settings that have similar types of
resistivity, permeability, and/or conductivity issues.
[0044] The material typically is obtained in an analyzable sample
or presented in an analyzable sample. In a general sense, an
analyzable sample can be any sample that has the necessary
characteristics that allow it to be analyzed using the specific
conditions of the inventive method to be practiced with the
material. Skilled persons practicing this invention will be able to
select such materials based on the other conditions of the method,
the teachings provided here, especially in view of routine
experimentation and other known principles. For example, the size
of the sample must be of sufficient size to provide enough material
to be analyzed. Additionally, the sample typically is handled in a
way so as to preserve material in the sample to allow volatile
substances to be released therefrom upon application of the
force(s) to be applied in performing the method of the invention.
Other conditions and features of collection, storage, and/or
handling of the sample may be selected so as to maintain the
structural and/or chemical stability of the sample and volatile
compounds contained therein. The sample also typically should be
sufficiently free of materials that might interfere with the
analysis. For example, the sample typically is collected and
maintained in a manner such that it is substantially free of
material from other sources that might "contaminate" the sample by
causing it to provide false information about the location it is
taken from and its contents.
[0045] In still another aspect of the invention, the sample is
obtained from a process that comprises the use of an oil-based mud.
In general, drilling muds may be water-based or oil-based.
Oil-based muds often can create difficulties for analytical methods
such as fluid inclusion analysis methods known in the prior art.
Those methods typically require application of high heat and/or
vacuum, such as, e.g., in a vacuum oven, applied over a long period
in order to deal with samples obtained with oil-based mud drilling
processes or risk interference from the oil base of the mud and/or
the oil material used for washing the samples. Such problems also
exist with respect to non-fluid inclusion analysis methods, such as
my other prior inventions. Methods in which high temperature and/or
vacuum is/are applied to remove oil-based muds can suffer from the
problem of also removing any endogenous hydrocarbons, organic
acids, and/or oil. The ability to analyze such samples with the
methods of the invention is yet another advantageous aspect of the
inventive methods described herein. Samples also or alternatively
can be obtained from water-based mud drilling operations, and in
some instances (as exemplified herein) samples can be obtained for
a site that was subject to both oil-based mud drilling and
water-based mud drilling.
[0046] As discussed elsewhere herein, samples may be sealed at or
soon following collection. In such aspects, about 0.5% to about 5%
of the volume of the sample may be made up of the target substance
or target-related substance. For example, about 0.75%-about 3.5%,
such as about 0.8% to about 3%, about 0.9% to about 2.75%, or about
1% to about 2.5% of the volume of the sample may be made up of the
target substance(s) (e.g., C5-C10 petroleum hydrocarbons) and/or
target substance-related materials. These amounts of target-related
substances are typically higher than the amount than would be found
in in materials only having such target substances or target
substance-related materials in fluid inclusions.
[0047] The amount of material collected or provided may be in
excess of the amount that can be the subject of analysis at any
time so as to provide assurance that there will be enough of the
sample material to perform repeated runs of the method, etc. Any
suitable amount of material can be used. A typical sample may be on
the order of about 100 mg, but may be as low as about 1 mg, about
10 mg, about 25 mg, about 50 mg, or about 75 mg. The maximum size
of the sample often is determined by either the sample container
size and/or the capacity of the mass spectrometry analytical
component of the device used in the method, if present. However,
under the right conditions and using the right type of device
samples as large as 1 g, 5 g, 10 g or even larger may be suitable
for analysis.
[0048] Typically, the sample will be collected from a material
having a relatively known location. The location usually will
include approximate depth information in addition to longitude and
latitude coordinates. Often the location may be a site of interest
in petroleum or mineral exploration, such as an expected or known
oil well, an oil well that has been previously deemed
non-productive, or a mineral mine, such as a gold mine.
[0049] In another aspect of the invention the sample is a fragment
of a core sample. Core samples are commonly generated in oil
exploration and related processes and are well understood in the
art. Analysis of core samples is considered important because of
the preservation of oil or other target substances in the material.
However, the process of analyzing core samples is often very time
intensive. Advantageously, methods of the invention can be used to,
e.g., to analyze fragments of core samples much more rapidly by,
for example, evaluating the hydrocarbon content of such core sample
fragments.
[0050] In most aspects of the invention, the sample is collected,
stored, and provided in a container. Such a "sample container" can
be any suitable type of container for maintaining samples in the
context of the method to be performed. In some aspects of the
invention the sample is either directly analyzed from the sample
container or is placed into a different analysis container prior to
analysis. Sample containers can include or possess certain features
that are advantageous in the performance of some of the techniques
described herein. Typically, the sample container is enclosed and
usually at least partially isolated from the environment (and
preferably substantially if not completely or essentially
completely isolated from the environment), so as to maintain some
portion of the volatile compounds in the sample over time, allowing
for the other steps of the method to be performed a period of time
after collection (and storage). In specific aspects, the sample
container is capable of preserving a majority of the volatile
substances in the sample at the time of insertion into the sample
container (and in some cases more than a majority such as about 65%
or more, about 70% or more, about 75% or more, about 80% or more,
about 85% or more, about 90% or more, about 95% or more, or even
about 99% or more (e.g., 99.5%, 99.9%, or more) of the original
volatiles are maintained) for a desired period of time (which may
be, e.g., 1 week, 2 weeks, one month, three months, six months, or
even a year or longer). The maintenance of volatiles in such
instances can be under typical, limited, or special conditions
(e.g., refrigeration or freezing may be required or desirable in
some cases, but in many cases samples can be maintained under a
wide variety of temperature conditions without much additional
care). In other aspects, the sample container need only be able to
maintain a sufficient level of volatiles to be able to be tested in
the method, which may be less than 50% of the volatiles in the
sample when the sample was loaded into the sample container. In
some cases, the amount of volatiles is more than about 65%, such as
about 75% or more, about 80% or more, about 85% or more, about 90%
or more, about 95% or more, about 97.5% or more, about 99% or more,
or even about 99.5% or more (such as about 99.9% or more) of the
volatiles present in the sample when placed in the sample container
are maintained. In some aspects samples may be maintained in the
container with one or more substances that reduce the likelihood of
biological activity that might reduce the probative value of the
sample.
[0051] In one aspect, the sample container comprises a feature such
as a seal, wall, cap, or the like (hereinafter simply referred to
as a "seal", unless context requires otherwise or unless otherwise
explicitly stated), which is selectively penetrable by a flow
channel device, such as a needle, such that volatile substances in
the container can be released when the sample container is
penetrated without significant loss of such volatiles. Thus, the
seal is typically of a material and construction such that it will
not release volatiles upon puncture or other formation of passage
through it to provide means for releasing the volatiles to the
other components of the system used to perform the method. Methods
for determining the integrity of the seal can be used optionally in
the method, as described below with respect to collapsible portions
of the container. Loss from or contamination into the container
from the puncture or other type of opening of or passage through
the seal will typically be non-detectable or will be of very small
amounts (e.g., less than about 1%, less than about 0.25%, less than
about 0.1%, or even lower amounts).
[0052] In another aspect, the methods, systems, and devices can be
practiced with containers that comprise a puncture-free method/step
and/or puncture-less component/system or device for providing
access to sealed volatile substances inside a sealed sample
container. For example, in one facet the invention provides a
system and method in which a sample container, such as a sample
tube, is able to be selectively open to the system, such as facets
wherein the sample containers are sample tubes within an enclosed
autosampler and the remaining portion of the system comes into
fluid communication with the container/sample upon positioning of
the sample tube into a position in which the open end of the sample
tube/container is allowed to interface with an entryway to the
remainder of the device/system, typically, for example by means of
an automates vacuum sealing connector, which may, e.g., cause an
O-ring to be tightened between the system and the open sample tube,
thus sealing the tube to the system without any puncturing or any
needle passageway. In this kind of facet, the system/device does
not permit significant loss of contents from the sample tube in the
system, as described elsewhere herein with respect to other sample
containers (e.g., less than about 5%, less than about 3%, less than
about 1%, less than about 0.5%, or even less than about 0.2% of the
contents are lost after placement into the sample container, in
this case in the system/device).
[0053] In another aspect, the sample container also or
alternatively comprises sufficient space beyond that which is
occupied by the sample itself, such that some portion of the
container can be filled with released volatiles. Accessible space
also often is provided for the needle or other channel forming
member or device to allow access into the sample container, in
aspects where a sealed container is provided. Thus, about typically
about 2-20%, such as about 3-15%, e.g., about 4-10% of the
container, when sealed, is left as open space providing space for
gas and also for flow channel device entry. The container may have
more open space before sealing to also provide room for the seal
(e.g., about 5-25% of the container may be designed to be open
before the sealing).
[0054] In still another aspect, the sample container also or
alternatively comprises a portion that is designed to be modifiable
under certain conditions, such as being collapsible under
mechanical pressure, such that the force of any sufficient
mechanical pressure applied to the sample container can be
transferred to the sample and thereby cause or increase the release
of volatile substances, preferably without disrupting the
structural integrity of the sample container in any manner that
would cause release of any amount or any significant amount of
volatiles that are released in the container (e.g., less than about
1%, less than about 0.25%, less than about 0.1%, or less than any
detectable amount of volatiles are released from the application of
force on the collapsible portion of the sample container) and/or
causing the contamination of the container space (and volatiles
contained therein) with substances from the surrounding atmospheric
environment (such as air in the laboratory). The method can
comprise monitoring pressure in the container or pressure in the
container as connected to the analytical device, as one measure to
make sure that no loss and/or contamination is occurring due to
leaks. Other methods also or alternatively could be performed to
ensure that such leaks of the container are not occurring, such as
analyzing compounds in the environment around the container using
conventional methods. As noted above, such techniques also can be
applied to ensuring the integrity of other aspects of the sample
container or other elements of the system that are used in the
practice of the methods.
[0055] In typical and preferred aspects, the sample container is
specifically adapted for use in one of the inventive devices
described elsewhere herein for performing the various methods of
the invention. Features that the sample container typically will
comprise in order to be suitable for use in such devices include
(1) a penetrable seal which is comprised of a seal material that is
both (a) inert with respect to and (b) is at least substantially if
not entirely impervious to the sample material and volatile
materials contained therein (by "inert" it is meant that the
material will not chemically react with the volatile materials and
the sample materials, and does not give off volatiles under the
conditions in which the method is performed, thereby modulating the
analysis), and (c) is adapted in shape and size to seal the body of
the container with respect to transmission of gasses and other
materials that might partially or entirely interfere with, corrupt,
or diminish the effectiveness of the analysis, and, preferably, and
(2) a body comprised of a material that can be subjected to forces
to be used in the method for drawing out of volatile materials,
which in preferred aspects includes crushing of the sample
container (and materials within the container) (e.g., the sample
container body comprises or is composed of a material that is
crushable under the force used by the device, allowing the sample
of the material to also be crushed while releasing volatile
materials from the sample into the container, the sample container
being constructed in such a manner and of such materials so as to
not be compromised, and so as to not lose its sealing properties on
being crushed as discussed elsewhere). The principle of inert
material discussed in this paragraph also typically applies to all
elements of the sample container and other elements of the system
used in the practice of the method. Thus, for example, tubing,
trapping devices, and analytical devices incorporated into the
system will similarly be selected based on being inert with respect
to the sample and volatiles expected to be present and subjected to
analysis.
[0056] In certain aspects, the method comprises multiple rounds of
crushing, such as crushing the sample container by application of
crushing and/or squeezing or compression forces, typically from
different directions. In still a further step, the method comprises
restoring the container, at least partially, to its original shape
after application of a crushing step or multiple crushing steps.
The step of crushing or compressing samples can be performed at any
suitable time. In one aspect, the step of crushing is performed
after the application of other forces that promote the release of
one or more volatile substances from the sample. In another aspect,
the step of crushing or compressing the sample is performed prior
to the application of other forces on the sample to promote the
release of volatiles, such as the application of pressure to the
sample. In still other aspects, as described elsewhere herein, the
step of compressing the sample can be performed independently of
extracting or releasing volatile compounds (and vice versa).
[0057] The preferred sample container is at least partially or
relatively flexible in design to allow for capturing a variety of
sample types under a variety of conditions. Methods of the
invention can vary considerably in terms of pressure, temperature,
gas content, and other relevant factors. The sample container and
other elements of the system typically are selected to be able to
operate under a wide variety of such conditions. Pressure
conditions are provided elsewhere herein that can help characterize
such suitability. Temperatures used in practicing methods of the
invention can also vary considerably, especially where high
temperatures are used to remove material and freezing is used as a
trapping method. In this respect, the overall system, including the
sample container, may see temperature ranges from about -273/-270
degrees C. ("degrees C" herein means degrees Centigrade) to about
500 degrees C., such as about -195 degrees C. to about 200 degrees
C. In many aspects, the temperature in the system will not exceed
or even possibly not reach 100 degrees C. In other aspects, the
temperature in the system will not exceed or possibly not reach 50
degrees C., particularly in the sample container. By remaining at
such temperatures more affordable materials can be used in the
practice of the method. Also, these extreme temperatures may not be
reached in all parts of the device. For example, heat may be
applied to the sample container, but freezing temperatures may only
be applied to the trap device.
[0058] The flow channel or needle is used to penetrate or otherwise
form a passage for the flow of gasses from the sample container (or
more particularly in typical embodiments a needle is used to
penetrate a seal component of or associated with the sample
container). In embodiments comprising the use of a needle, the size
of the needle typically is selected such that it provides
sufficient flow of volatiles from the sample container to the rest
of the system but is not so large as to cause puncturing of the
seal and release of seal material (or other portion of the
container) into the interior of the sample container. A needle used
in the methods herein can have any suitable configuration of inlets
(holes) to receive the gas. A single hole, placed in the side, or
two holes, placed on each side, of the needle, is typical. Side
placement of the needle can help ensure that the needle inlet does
not become clogged after passage through a seal or sidewall of the
container. A type 5 needle (by Hamilton), for example, provides
such a balance with respect to exemplary devices described
herein.
[0059] As noted above, sealed samples can be stored for significant
periods of time and still be successfully analyzed using the
methods of the invention. Some volatiles can be trapped in
hermetically sealed voids in solids, such as fluid inclusions in
rocks. In some embodiments, such volatiles can be analyzed years or
decades after the sample is collected. The volatiles hermetically
sealed in the solid can be released by crushing the solid, or by
thermally heating the solid until the volatile filled voids
decrepitate.
[0060] Other volatiles can readily escape from their solid, liquid
or gaseous host. Such volatiles include oil, water, and gas in
pores in drill cuttings or core, or within the drilling mud used by
the well. It will typically be desirable that such solid and liquid
samples are sealed as quickly as practically possible to permit the
most representative analyses of the oil, water, and gas in the
Earth's interior. As demonstrated and discussed elsewhere herein,
the methods of the invention can be practiced with old, exposed
materials, in which some or even significant loss has occurred, but
better results are often obtained with samples that are sealed
within a short period of time from the sample reaching the surface
or being exposed to changed atmospheric conditions that would allow
for release of relevant substances.
[0061] In one aspect the inventive methods are practiced without
application of a significant vacuum or pressure on the sample prior
to performance of the method. My prior inventions and other prior
art methods often will apply significant vacuum or pressure and/or
significant temperature to samples prior to analysis of the
materials. The lack of such a step in certain aspects of this
invention is yet another way in which such aspects are
significantly distinguishable from the prior art.
[0062] While sample containers that can be crushable or otherwise
compressible are often preferred, a large variety of sample
containers may be adequate for samples that do not require
mechanical disruption (e.g., glass vials, graphite tubes, or other
containers that are impermeable and inert) in the practice of
certain aspects of the inventive methods. Thus, for example, if
there is to be no mechanical disruption either glass vials or
sealed metal tubes can be used as sample containers. Various hoses
made of rubber or other polymers might also or alternatively
suffice if they can be hermetically sealed. Even Mylar or plastic
bags may suffice for some applications. In some aspects of the
invention containers also can be comprise or primarily, nearly
entirely, or entirely be made from carbon fibers. Indeed, any
container that can be hermetically sealed might be sufficient,
depending on the nature of the bulk material being captured.
[0063] Commonly, the sample container comprises a septum or a cap
(e.g., a synthetic rubber or nitrile cap) that is inert and through
which a suitable flow channel device such as a needle can be
readily passed while maintaining the seal's integrity. In such
aspects, the volatiles purged from the sample will enter the inlet
lines through the needle. Such elements of the sample container are
optional. In another exemplary embodiment, the sample container is
sealed using a compression fitting that can be automatically
applied, with subsequent rupture of the sample container to release
the volatiles into the system's inlet. Another approach that may be
more appropriate in some instances would be to insert the entire
sample container into a hermetically sealed chamber that is
attached to the inlet system, followed by subsequent rupture of the
sample container to release the volatiles. The sealed sample
container could be introduced automatically one at a time through
an appropriate port, or an individual sample or multiple samples
could be preloaded and sealed into part of the inlet system.
[0064] If the sample is to be crushed and is on the exterior of the
inlet system connected by a needle through a septum, cap, or some
other means, such as a remotely controlled compression fitting, it
can be desirable that the container can be crushed without leaking,
and that any motion of the sample during crushing does not break
the seal between the sample container and the inlet system. The
selection of parameters for sample containers, seals, other
elements of device, and compression/crushing methods in general
will be selected such that a seal is maintained and there is no
undesirable loss of volatiles or material or contamination thereof.
A brass cylinder sealed on the bottom with a neoprene plug and
sealed on the top with a nitrile cap, for example, can be a
suitable sample container. However, other metals and other sealing
methods may be employed in the sample container or systems/methods
of the invention. For instance, a brass rod could be partly drilled
out to make a vessel sealed on the bottom, thereby eliminating the
need for the neoprene plug. Similarly, the cap could be made of a
variety of compounds, however Nitrile has very good sealing
properties for hydrocarbons and most other volatiles.
[0065] It is typically important that if a cap is used to seal the
sample container that it can be hermetically sealed to the body of
the sample container. This can sometimes be achieved by simply
having the cap's resting diameter be sufficiently smaller than the
tubes diameter so that the cap needs to be stretched over the tube
or fit into the tube that forms the body of the sample container.
Stretching in this manner might by itself typically result in a
sufficient seal. If not, then additional methods must be employed
to affect a hermetic seal between the cap and the tube, such as
applying a compression device such as a hose clamp or zip tie or a
metal ring having a diameter greater than the tube but less than
the diameter of the cap when covering the tube, around the outside
of the cap. Other methods of sealing the cap to the tube can
include applying glue, or epoxy, or wax, or grease, or some other
sealing substance between the cap and the tube. It is also possible
instead of a cap to use a septum crimped to the top or some other
part of the sample container for a needle to pass through, or even
a polymer plug, such as a neoprene plug used to seal the bottom of
sample containers. For a sample container that is secured to the
inlet system by an outer compression fitting, or some other means
such as a screw fitting as on a hose (or a threaded cap), that is a
larger than a needle can form a channel or flow path between the
sample container and the inlet system. Such a sample container
adapted to be in direct material communication with a wider
diameter inlet system can be sealed using a wide variety of sealing
material including metals, polymers, glass, even such exotic means
as a salt or sugar plug, glue, or other adhesive or sealing
material. The sealing material typically will make a hermetic seal
after the sample is captured up to the time it is ruptured, and
must be amenable to rupture after attachment to the inlet system.
Similarly, sample containers that are loaded entirely into the
inlet system generally will be hermetically sealed following
loading of the sample, and usually will maintain that hermetic seal
until somehow ruptured or made permeable to the substance(s) of
interest at the appropriate time inside the inlet system.
[0066] As exemplified by the foregoing passages, it can in some
aspects be advantageous and/or important that the overall system
(sample container, inlet, or other elements of the system) are
configured and constructed such that the overall system maintains
its integrity, particularly with respect to the sample and
volatiles released therefrom, upon the application of any forces
applied in the method, such as any crushing force. An example of
such an approach is the use of a needle-associated slug, as
exemplified elsewhere herein. In aspects where application of a
crushing force causes parts of the sample container to move, become
deformed, or otherwise become displaced, such movement may permit
the hole that the needle passed through to become enlarged, which
might, if not addressed, allow undesirable release of materials
from and/or contamination of the system/sample container. A slug
associated with the needle, such as by use of a compression spring
placed around the needle, forcing intimate contact between the slug
and the cap or seal, can assure the user that any such expanded
hole formed in the cap or seal will still not permit such release
or contamination. However, other approaches can similarly be used
to ensure that the entire sample container/device system maintains
the integrity of the material, depending on the configuration of
the device and sample container (and steps of the method) and any
released volatiles and the invention is not limited to this
slug/spring approach. For example, if high temperature is applied
to the sample container, the sample container and inlet may be
configured and composed such that the application of such high
temperature does not allow the formation of any cracks or openings
that would similarly allow for undesirable contamination or
release.
[0067] In one aspect, the crushing of a sample container and sample
contained therein is used to assess the ductility (and/or porosity)
of the sample and, correspondingly, the material. In a method in
which a material of relative standard strength (in terms of
crushability under a relatively fixed amount of crushing force)
(such as by using the same quality of material in the same
thickness, etc., within very small variations (e.g., about 10%
variation or less, such as about 5% variation or less, such as
about 1% variation or less in thickness and other relevant
characteristics), is employed with a standard measure of sample
(again, given the ability to have similar variability in the
amount), the amount of collapse of the container, reflecting also
the crushability of the sample, can be correlated to either the
strength of the material and/or the ductility of the material
(and/or porosity of the material). Such methods can be advantageous
where the method is performed in connection with oil fracking or
similar methods in which ductility of the material is a very
important feature of the material.
[0068] Mapping the ductility of samples versus measured drilling
depth in vertical well, or in a horizontal well, can provide
information as to which sections of rock are most likely to have
low risk of fracking failure. Fracking failure occurs when the
rocks that have been hydraulically fracked do not have sufficient
mechanical strength to maintain the induced fractures open
following the injection of a proppant, usually sand. This aspect of
this invention therefore is termed "frackability", as an advantage
of this aspect of the invention is permitting practitioners of the
method to map those sections of rock drilled by a petroleum well
that will maintain open fractures following fracking and proppant
injection. This can be especially critical nearest to the borehole,
since if the fractures near the borehole do not remain open, no or
only a very diminished amount of oil and/or gas can be
produced.
[0069] One realization of this aspect of the invention is to
measure a container, such as a sample tube as described herein
loaded with cuttings, after squeezing with a known force, with a
micrometer or other appropriate measuring device. Such a method can
be performed manually after the sample has been squeezed, or can be
done automatically as part of the analytical process using a device
such as a linear translator that mechanically monitors how far the
pneumatic pistons are extended after squeezing the sample is
completed, or a device such as a laser ranging instrument, also to
measure the total extension of the air piston, or other squeezing
means, after the sample is totally squeezed to its final
thickness.
[0070] Real time measurement of the squeezing process by an
appropriate measurement means allows additional information to be
collected that provides useful and necessary information for the
design of a optimally successful fracking job. This includes
measuring how the air piston or other squeezing means deforms the
sample as a function of time and/or the amount of pressure applied.
The sample deformation may be relatively rapid, or relatively slow.
The deformation may be a smooth continuous process, or may be a
series of discontinuous forward lurches. Also of interest is how
far the piston is pushed back by the sample after the pressure is
released from the air piston, that is how much does the sample
recover. The collection of these data during the squeezing process
will allow for the calculation of various parameters vital to a
successful fracking job, including Poisson's Ratio and Young's
modulus.
[0071] Analyses of these parameters using the current state of art
in the industry usually requires the expensive acquisition of a
conventional core, or rotary sidewall cores, followed by expensive
and time-consuming measurements at a laboratory usually some
significant distance from the well. Often it is months after the
well is drilled before the results of these other measurements are
known.
[0072] Frackability from petroleum drilling cuttings can be rapidly
determined either in the lab or on the well site. Turnaround time
for transport of samples to the lab followed by analyses can be
less than 24 hours. This is fast enough for the data to be used in
deciding the final manner in which the well will be completed, such
as what zones will be perforated, or where a horizontal lateral
will be landed following the drilling of a vertical pilot hole.
[0073] Even more timely results can be had by measuring
frackability of the well site while the well is drilling. This can
be done by manually collecting samples and then loading in an
instrument at the well site for analyses. In another aspect of the
invention, frackability can be determined at the well site using an
automatized instrument that collects a sample of drill cuttings and
squeezes them and monitors the deformation. Such an automated
apparatus would not require loading the cuttings samples into a
container. The cuttings can fill a collapsible compartment in the
well site frackability apparatus. Following filling of said
compartment with cuttings the squeezing mechanism of the apparatus
squeezes the cuttings while the amount and systematic of the
deformation of the sample is recorded using a linear translation or
other type of measuring meter. The data thus collected would then
be stored on a computer, and can be instantly integrated with other
drilling parameters generated by other instruments on the well,
including logging while drilling tools, such as gamma ray logging
while drilling, rate of penetration, weight on bit, mud log shows,
etc.
[0074] Real time frackability data can be combined with other
real-time data to determine the optimum way to drill the well. The
data can be used to help steer lateral horizontal wells to stay in
the optimum formation.
[0075] In one aspect, the invention provides a method for analyzing
the frackability (ductility or hardness) of a material, such as a
geologic formation, which comprises the steps of (a) providing one
or more analyzable samples of the material, (b) subjecting the
sample to one or more forces that are capable of compressing
material of a given hardness or ductility, and (c) determining the
amount of compression of the sample caused by the one or more
forces. The analyzable sample typically, but not necessarily, will
be from or associated with a petroleum well or petroleum
exploration. The most basic form of the frackability method is
distinct from prior approaches used to assess hardness of a
geologic material, which either depend on scratching (e.g., the
classic Mohs scale testing) or penetration of a point of the
material or point contact with a surface of the material (such as
by using the Schmidt rebound hammer), although such methods can be
combined with the basic frackability method. In one aspect, the
compression force is applied to at least an entire side of the
sample. More typically, the compression force will be applied to
multiple sides of the sample contemporaneously (within 2 minutes,
within 1 minute, within 10 seconds, within 5 seconds, within 3
seconds, or within 1 second of each other), and, most often,
simultaneously. Frequently, the compression force(s) will be
applied isotopically, that is to say that it/they will be applied
to all sides of the sample contemporaneously or simultaneously.
Where advantageously combined with other methods of the invention,
the compression study will be conducted in a compressible
container, as exemplified elsewhere herein. The sample often is
either a cutting or taken from a core sample associated with a
petroleum well or petroleum exploration. Thus, in many aspects the
size of the sample will be the size of a cutting, as explained
elsewhere herein. In one aspect, the method is performed on
cuttings that are associated with petroleum-associated mud. In
other aspects, the method comprises washing the sample prior to
crushing.
[0076] A further distinction in the typical application of the
frackability method and methods of assessing hardness of geologic
materials in the prior art is that the frackability method,
especially when applied to cuttings, is applied to a large number
of materials (at least 10, typically at least 20, and often more,
such as at least 25, at least 30, at least 40, at least 50, or
more) that are obtained from different depths and/or different
locations within a relative zone of depth, and frequently such
materials are brought to the surface within the relatively short
amount of time that is required for petroleum drilling (e.g., about
1 day to about 12 months, such as about 1-300 days, about 1-250
days, about 1-240 days, about 1-200 days, about 1-180 days), such
that the samples comprise a number of samples obtained during this
period (e.g., a majority of the samples are obtained within 200
days of each other or at least 20, at least 30, at least 35, at
least 40, at least 50, or more, of the samples in the analysis are
obtained within at least 240, at least 180, at least 120, at least
90, or at least 60 days of each other). Currently, assessments for
fracking suitability have typically made using either (1)
minerology assessments, which determine the mineral structures
present in the drilling area or potential drilling area through
sampling, (2) x-ray diffraction methods to similarly assess the
geologic content of the area (within the detection limits of that
method), and (3) assessing the total organic content of the exposed
area of the material. These practices can be combined with the
compression frackability methods provided by this invention, in
certain aspects, to provide additional information about the
material. However, in another aspect, compression frackability can
be performed as an assessment method without employing any of these
methods.
[0077] A collection of samples evaluated in the frackability, such
as cuttings, can consist entirely of samples obtained from
locations in the material that are at least about 0.5 feet apart,
and typically (but not necessarily) up to about 100 feet apart from
one another (e.g., they can be from depths of a well that are at
least 0.5 feet apart, at least 0.75 feet apart, at least 1 foot
apart, or even further apart, such as at least 18 inches apart or
at least 24 inches apart), or the set of samples can substantially
consist of (e.g., at least 85%, at least 90%, at least 95%, at
least 97%, or at least 99%) samples obtained from locations
characterized by such differences, or the set of samples can be
characterized in that a majority of the samples were obtained from
locations having such differences in space, or at least a large
proportion (such as at least about 10%, at least about 20%, at
least about 25%, at least about 33%) of the samples were obtained
from locations that have such relative spatial separation. In view
of the possibility of lateral drilling the separation between the
samples also or alternatively could be in the same relative zone of
depth (e.g., within the same 500 ft, 400 ft, 350 ft, 300 ft, 250
ft, 200 ft, 150 ft, 100 ft, 50 ft, 30 ft, or 25 ft vertical zone).
In some aspects, multiple samples from approximately the same
location are tested, but the set comprises a number of samples from
different locations (e.g., at least 10, at least 20, at least 30,
at least 50, at least 100, at least 150, at least 200, at least
250, at least 300, at least 400, at least 500, at least 750, at
least 1,000, or more samples, from locations in the material that
are at least about 0.75 ft separated from each other). The number
of total samples used in such a method will typically be greater
than about 10, such as greater than about 20, and often can be
significantly more samples, such as at least 50, at least 100, and
can range from 10-5,000, 10-3,000, 10-2,500, 15-3,000, 15-2,500,
20-3,000, 20-2,500, 25-3,000, 25-2,5000, 25-2,000, 20-2,000,
10-2,000, 20-1,500, 25-1,500, or 10-1,500 samples, The total area
of assessment can be significant, such as at least about 0.25
miles, 0.33 miles, 0.5 miles, 0.75 miles, 1 mile, 1.25 miles, 1.5
miles, 1.75 miles, 2 miles, or more, in depth and/or in horizontal
area, reflecting lengths of modern petroleum wells. Thus, the
frackability methods of the invention can provide a relatively fast
map of the suitability of fracking a well site. In some respects,
the entire analysis is conducted near the well site (such as within
200 feet of the well site). This can be achieved by using devices
of the invention that compress material near the point of
separation of cuttings and muds, for example, in petroleum
drilling.
[0078] In some aspects, the compression frackability methods of the
invention are combined with the other methods described herein for
assessing hydrocarbon content of a material through release of
volatile compounds, such as organic acids, which may be released
using the methods described herein (e.g., application of gentle
vacuum, trapping, and optionally analysis by sensitive methods such
as mass spectrometry analysis). In other aspects, the frackability
methods of the invention and the volatile compound analysis methods
of the invention are practiced separately. Similarly, for the
devices of this invention, such devices can comprise combined
frackability and volatile compound analysis components/systems, but
the invention also provides devices that comprise these functions
as individual features.
[0079] Some aspects of the invention, particularly those in which
released volatile compound analysis will be performed as a part of
the inventive method, are characterized by comprising a step in
which sample material is stored quickly, and typically in a sealed
manner, after arriving at the surface or otherwise being exposed to
normal atmospheric conditions. For example, at an oil well site
such a method can comprise collecting cuttings in a sealed
container within a short amount of time after such cuttings reach
the surface. The time for collection can vary with the nature of
the sample, the method to be applied, and the target material(s)
that are sought to be identified by the method. In an exemplary
aspect of the invention, the samples are sealed in a sealable
container in about 5 minutes or less, but more typically the time
will be about 3 minutes or less, about 2.5 minutes or less, about 2
minutes or less, or even about 1.5 minutes or less, such as about 1
minute or less. Samples can be subject to washing immediately
before sealing in a sealable sample container. Sample washing can
be carried out by any suitable method. More generally, but not
necessarily, cuttings or other materials typically are stored such
that volatile compounds contained therein are not lost below limits
detectable by the method. Volatile gasses and chemicals that
rapidly expand under atmospheric pressure and non-constrained
conditions, such as petroleum-related hydrocarbons, can be readily
released from such materials once they reach the surface.
Accordingly, it is advantageous to store materials to be analyzed
such as cuttings within one or more containers that will ensure no
release or little release of such substances during the time the
material is to be stored and/or transported. In a preferred aspect,
the materials are stored in one of the devices described elsewhere
herein, and most preferably such a device is configured to fit
securely within one of the analytical devices of the invention
described further elsewhere herein, such as by mating with an inlet
or by using a flow channel device, such as one of the needle
devices discussed herein.
[0080] A filter material also can be added to the sample container.
Any type of suitable filter material can be used. Suitability in
this respect generally means that substantially all (e.g., at least
about 95%, such as at least about 99%, or at least about 99.9%) of
the material (excluding the volatiles released from the material)
is maintained in the interior of the sample container and does not
enter or come into contact with the flow channel or inlet. Simple
filter materials such as cloth materials and cotton pellets have
been demonstrated to be suitable for this purpose. These materials,
as with other materials used in the sample container and throughout
the system must be inert with respect to reacting with volatile
chemicals and emitting materials that would interfere with the
analytical aspects of the inventive methods.
[0081] In one aspect of the invention, the sample(s) that is/are
analyzed in the method is or comprises a drilling mud. Muds have
been discussed elsewhere herein. The mud can be an oil-based mud or
a water-based mud. The analysis of muds typically means that more
than one mud samples are taken. This is because material can be
maintained in a mud over several re-uses of the mud (or passages of
the mud to the drill bit point and the surface where a sample might
be taken). Accordingly, samples may be taken at points that
correspond with an "up mud" (mud arriving at the surface) and a
"down mud" mud going back into the well, which will help to
identify changes in the mud over time, aiding in the analysis of
the material through studying the mud. In one aspect, the method
comprises the analysis of mud materials and cuttings. In still
another aspect the method comprises the analysis of mud materials,
cuttings, and/or fragments of core samples, such as samples of each
of these categories taken from a petroleum well or petroleum
exploration site.
[0082] The material and sample are typically a solid (as in the
case of a cutting), but in other aspects of the invention the
sample and/or material is a liquid or a gas, and in still other
aspects the sample and/or material is a mix of two or more of a
solid, liquid, or a gas, or a combination of all three forms of
material. For example, in an industrial setting, samples can be
taken of the air to ensure that the amount(s) of certain compounds
(e.g., benzene) are within certain levels. In still another
embodiment the method is applied to look for seeping, such as
gasses seeping into and/or out of a geological formation.
Geothermal activity also can be assessed by the method. In another
aspect, the method can be practiced with a liquid, such as water,
to assess the level of certain substances in the liquid (such as
contaminants in water samples). As noted elsewhere the material can
be of natural, synthetic, or semi-synthetic origin, and may be
generated from a variety of origins and/or settings, such as
industrial solids, soft materials, liquids, and air, or other
gases.
[0083] In preferred aspects, the method is applied to analyze the
volatile compound content of the material. Volatiles in rocks
typically contain important information used for petroleum,
geothermal energy, and mineral exploration and production.
Volatiles in rocks can also be used to determine the suitability of
quarried stone for road and building construction. Volatiles in
rocks and soils may also provide information beneficial to
ecological and environmental studies. Volatiles in solids that form
as a byproduct of various industrial or civil processes, such as
scales that can form in the casing of oil, gas, and water wells,
can provide information that may help design processes to inhibit
the formation of such unwanted solids. Volatiles in man-made solids
such as bricks, concrete, ceramics, glass, and plastics can be used
to ascertain problems in their manufacturing process, or to
evaluate their utility for various applications. Volatiles that
occur in solids that form in natural biological systems, such as
bone, teeth, kidney stones, finger and toe nails, may provide
insights that could help to maintain or improve the health of the
individual or community from which these solids originated.
Volatiles in softer tissues from plants and animals, including
humans, may also offer diagnostic information that may be useful to
the health of the source organism. Such methods may have
application in testing in food safety testing, food viability, food
storage, and/or shelf-life, or the like. Volatiles in industrial
and natural liquids also contain a wealth of information that can
impact the success and profitability of petroleum, geothermal
energy, and minerals exploration and production; the efficiency and
profitability. of manufacturing and other industrial processes; and
the health and well-being of the environment, organisms and
communities. Various explosive products may also have distinct
volatile signatures that could be detected with the device
described herein, thus volatile monitoring of air or solids may
have benefits in keeping people, communities, the military, and law
enforcement secure.
[0084] In one aspect of the invention the sample is taken from an
outcrop and the material comprises an outcrop. Outcrops are
geologically important formations. In one aspect, outcrops
(outcroppings) are used as a comparator to subterranean materials,
such as materials obtained from a mine or drilling site. Such
materials may also contain evidence of materials seeping to the
surface.
[0085] The material typically is dry, but in some aspects of the
invention is moist or even wet (e.g., in the case of a liquid or a
mud). In some aspects of the invention it can be important to
ensure that the amount of a liquid, such as water, in the material,
is not too high so as to overcome the capacity of the mass
spectrometry device. However, in general, this is not a limiting
factor, and the skilled artisan will be able to assess if any such
situation arises. As already noted herein, the material, and thus
the sample, will typically contain one or more volatile substances
that will either passively release or be released upon the
application of one or more forces on the sample. In either case, a
gas will be released from the sample that contains one or more
volatile substances, although, as discussed elsewhere herein, the
sample can also contain non-volatile substances, which may also or
alternatively be collected, and considered, as part of the
analytical aspect of the inventive method. The nature of the
volatile substances contained in the sample can vary considerably
and the inventive methods can be practiced with various types of
volatile compounds. In specific aspects, however, the sample and
material contain a significant amount of one or more specific
target substances. For example, in the case of drill cuttings,
taken from petroleum production of exploration sites, the sample
will contain detectable amounts of one or more species of C1-C20
hydrocarbons and related compounds that contain oxygen, nitrogen,
sulfur or other heteroatoms; organic acids (e.g., C1-C5 organic
acids, particularly C1-C3 organic acids, and most commonly acetic
acid, carbonic acid, and/or formic acid); and/or one or more
inorganic gasses, such as hydrogen, helium, carbon dioxide, carbon
monoxide, water, nitrogen, argon, oxygen, hydrogen sulfide,
carbonyl sulfide, carbon disulfide, and/or sulfur dioxide. In one
embodiment, the sample comprises C1-C15 hydrocarbons, such as
C1-C14 or C1-C12 hydrocarbons and the method comprises analyzing
one or more of such hydrocarbons. In still another aspect, the
sample comprises C1-10 hydrocarbons and the method comprises
analyzing one or more of such hydrocarbons. In aspects that are
often preferred the invention also or alternatively is
characterized by the detection of acetic acid, carbonic acid,
and/or formic acid contained in the sample or formed from
application of one or more forces on the sample in the practice of
the inventive method. In this respect, the sample can be
characterized as comprising one or more compounds that form such
compounds, or by having material that can form carbon dioxide,
carbon monoxide, methane, and/or water.
[0086] In another facet, the inventive methods provided herein can
be characterized in that such method comprises conducting an
analysis of the sample for one or more substances containing a
carbon chain of five or more, such as six or more, or seven or more
carbon atoms. In some cases, the method comprises heating the
sample or gasses to assist with the analysis of longer chain
hydrocarbons or other carbon chain-comprising compounds, such as
hydrocarbons having a backbone of more than 10 carbon atoms. For
example, the method can comprise heating the sample or gas (or the
device containing either or both) to about 130.degree. C. or more,
about 140.degree. C. or more, or about 150.degree. C. or more, to
assist with the analysis of such longer-chain hydrocarbons. In this
and other respects, the method can comprise controlling the
temperature during which some or all of the process is performed,
such as the temperature at which gasses are released and/or
analyzed by the analytical processes of the method. Such methods
typically can comprise heating the entirety of the system from the
inlet, through to the trap, to the mass spectrometer, and through
to the exit. In other aspects, it is preferred that the method is
generally performed at room temperature, although in such aspects
it may also comprise using freezing as a means for trapping
volatiles and/or applying heat to release compounds from a freezing
trap mechanism or media.
[0087] In some aspects, the invention is characterized by not
creating new volatile compounds in the sample, such as forming
volatiles from hydrated minerals (where water is a part of the
crystal structure, such as silicate clay minerals; hydrated oxides,
such as brucite (MgOH2) and goethite (FeOOH); and other
water-bearing mineral substances such as hydroxyl apatite; etc.) or
where, e.g., carbon dioxide is part of the crystal structure (such
as calcite (CaCO.sub.3), dolomite (CaMg(CO.sub.3).sub.2), and
siderite (FeCO.sub.3)); and solid and liquid hydrocarbons not
volatile as a gas under the analytical conditions in which the
methods of the invention are performed, such as C20 alkanes or
various bitumins or kerogens; or any other substance that is
normally not a gas or normally emits a gas under such
conditions.
[0088] In practicing methods of the invention one or more gasses
is/are typically released or extracted from the sample of the
material. In some contexts, the gas can be released passively
(without application of force or without application of a
significant force); e.g., by exposing the sample or the container
comprising the sample to a release channel or release passage, such
as a needle or similar device which penetrates the container
containing the sample. In other contexts, as noted elsewhere
herein, the methods also or alternatively can comprise applying
energy to the sample, such as by mechanical force, e.g., crushing
of the sample or crushing of a container that has a crushable
portion and that contains a crushable sample. In either case, the
gas or gasses are released from the sample of material and then are
allowed to flow such that one of the further steps of the method
can be performed on such gas. The amount of time required for the
gas to be release can vary with the conditions of the method,
including the material, whether or not forces are applied to the
sample, the time in which gasses are permitted to be released from
the sample, and the sensitivity of the analytical methods performed
on the gasses. Using the guidance provided herein skilled artisans
will be able to determine these conditions. For samples that are
analyzed at atmospheric pressure without the application of force a
time of about 1 second may be sufficient, for example. Longer or
shorter periods of time may be suitable, but such a relatively
short period may be desirable. Longer periods may cause the sample
to be under lower pressure conditions because of the relatively
lower pressure condition of the device.
[0089] In many aspects of the invention volatile substances are
extracted from a sample by subjecting the sample to various levels
of vacuum. For some samples, important additional information is
obtained by subjecting the sample to a range of increasingly lower
pressures, in other words to increasingly higher levels of vacuum,
and analyzing the chemistry of each individual aliquot extracted at
each individual extraction pressure. This has proven to be
especially useful for solids, particularly for various rock samples
including outcrop, core, and cuttings samples as applied to the
exploration for and production of oil and gas. Depending on the
sample and the problem being addressed various other processes may
be applied to the sample prior to any vacuum extraction, in between
vacuum extraction steps, or even during a vacuum extraction step,
as will be discussed further herein. In one example, another
process that can be applied, and which is described elsewhere
herein, is crushing or squeezing the sample or applying any process
that mechanically disrupts the solid sample. Other processes that
might disrupt the sample include sawing, or tumbling, or exposing
to vibrational energy at any number of frequencies. Another process
that could be employed is heating the sample; one effect of which
can be disruption of the sample by thermal decrepitation of fluid
inclusions and/or other structures in the sample. Chemical
processes and/or application of energy also or alternatively may be
applied to the sample in the performance of the method, such as,
for example, applying an acid to the sample so as to dissolve
certain substances. It is also possible that in some instances a
combination of two or more of these or other disruptive processes
may be usefully applied in the practice of the inventive
methods.
[0090] The method also may include one or more steps performed
before release of gasses, or between release of gasses (in methods
in which there are multiple release steps or multiple samples
analyzed). In one aspect, the method comprises purging some amount
of air from the sample, e.g., by application of vacuum. In such
embodiments the time the vacuum purge is applied will generally be
such that the amount(s) of volatiles that are purged with the air
is sufficiently small to justify the purging step. This may
comprise, for example, only 1 or 2 second application of vacuum
pressure, so as to lower the pressure from about 1000 millibars to
about 50 millibars (but these are only exemplary figures). However,
such a purging step can be important where the presence of air as a
contaminant will interfere with the analysis. This may be important
with respect to analysis of older samples contained in open
environments.
[0091] In a further specific aspect, the inventive methods can
comprise purging the sample, which may be a sealed sample, and
replacing the purged air with another gas, such as argon, nitrogen,
or helium, or any other suitable gas as determined by the specific
advantage gained for the specific problem being addressed and the
specific host solid and specific volatiles being analyzed. argon is
typically preferred as nitrogen and helium may be relevant in the
analysis of the sample.
[0092] These steps of purging (and optionally replacing) air or
other surrounding gas provides a mean of removing potentially
interfering substances in the air or other gas in which the sample
is contained, which might provide false signals in the analysis
(e.g., confusing methane with oxygen or nitrogen species found in
air). Other methods of accomplishing the same goal may be available
in the art and likewise suitable, but this method is preferred in
many aspects of the invention. For example, in one alternative, the
air or gas in an inner sample container is displaced with a liquid,
such as a diffusion pump oil, and the inner sample container placed
in a surrounding, outer container. The inner sample container
comprises or typically is entirely made of a material that can be
crushed or compressed by application of a force. A vacuum is
applied to remove any air from the surrounding container, creating
a vacuum condition in the space formed by the surrounding
container, and the entire sample container sealed. A force that
compresses or crushes the sample in the inner container is applied,
breaching the inner container and releasing volatiles into the now
exposed outer container. Such materials can then be subjected to
further analysis in accordance with the inventive methods described
herein with little risk of interference from substances in air,
etc.
[0093] The rapid purging of air from the sample, and rapid
replacement with argon or other gas prior to crushing the sample
can be particularly relevant in analyzing samples relevant to oil
and/or gas exploration. Generally, these methods are applied to
older samples maintained under open conditions, as there is a
trade-off in terms of loss of volatile substances in applying the
purging methods. Thus, for sealed samples, such methods may not be
practiced.
[0094] Purging (and purging and replacing processes) can facilitate
the mass spectrometer analyses of very small amounts of certain
substances, such as methane, using mass 15 for the CH3.sup.+ ion,
by removing nitrogen and oxygen. The lower resolution of many
quadrupole mass spectrometers makes it difficult to analyze trace
methane using mass 15 in the presence of major amounts of nitrogen
with a major peak on mass 14 and oxygen with a major peak on mass
16. Purging and replacement of air with other gases may have other
benefits. Replacement of air with krypton, having mass 86, would
solve the methane interference issue as does argon, but could also
aid in the extraction of some recalcitrant volatiles in the solid
by imparting a much greater amount of energy in collision with the
lighter gases present as the sample's voids are evacuated.
[0095] Most purging steps are completed quickly, especially when
the step comprises the removal of air in the system by means of
quick vacuum (versus flowing of an inert gas or a combination of
both types of steps). For example, in one aspect the purging
process is complete in about 10 seconds or less, such as about 5
seconds or less, about 3 seconds or less, or even about 2 seconds
or less. In the case of a quick vacuum purge, application of such a
step for less than about 3 seconds, such as less than about 2
seconds, less than about 1.5 seconds, or even 1 second or less can
be advantageous. Another way to characterize such a step in some
aspects is that the vacuum purge step results in a loss of less
than about 5%, less than about 2%, less than about 1%, or even
lower losses (e.g., less than about 0.5%) of the oil and with
respect to gasses the losses are less than about 10%, less than
about 7.5%, less than about 5%, less than about 3%, or less than
about 1% of the gas present at the time the sample is introduced to
the system. Purging is typically performed prior to crushing or
squeezing of materials, or other application of forces to the
sample. At the well site, samples may not be purged as nearly all
information can be converted into data, especially with the use of
control sampling devices/systems that are used to calibrate the
system (with respect to gasses that are at the site and not
associated with the samples). For sealed samples, the method also
may lack purging, as this may result in data loss. As such, purging
steps are often optional, but can be useful when there is a
determination that there could be a risk of an interfering
signal.
[0096] Depending on the problem being addressed by the analytical
method, it also or alternatively may be advantageous to heat or
cool the sample prior to volatile extraction. Heating or cooling of
the sample can be performed alone or with crushing and/or purging
(or purging and replacing the air or other surrounding gas). For
instance, if volatiles in water ice were to be analyzed, the sample
would need to be held at a cold enough temperature to keep the ice
frozen during volatile extraction and any purging and gas exchange
for air preceding crushing. A temperature of about minus 50 degrees
Centigrade might be needed in this example to keep the ice from
sublimating in response to the applied vacuum. A similar process
could be advantageous in the analysis of gas hydrates, otherwise
known as clathrates.
[0097] Centrifuging also or alternatively can sometimes be an aid
to volatile extraction. Centrifuging an upright sample prior to
volatile extraction, for example, can cause the vertical
stratification of volatiles in the container, gases would migrate
to the top, and oil would in general form a layer on top of water.
This can be particularly useful in the analyses of volatiles in
drilling muds from oil and gas exploration and production wells.
Centrifuging following crushing can sometimes also have similar
advantageous effects.
[0098] After all preparatory processes, if any, are complete the
volatiles typically are extracted from the sample by reducing
pressure on the sample by exposing the sample container to an inlet
system that is under static vacuum and is not being actively
pumped. The inlet system typically is sealed off to vacuum pumps at
this point in the process, having been previously evacuated by
vacuum pumps. Pressure is reduced on the sample by opening a valve
between the sample container and the inlet system allowing gas to
pass from the sample through the needle or other flow channel
device into the inlet system. During a multi-stage extraction, at
increasing levels of vacuum for each extraction, the first
extraction results in a resulting pressure on the sample and in the
inlet system that is determined by the gas pressure in the sample
and the sample container, the void volume in the sample container,
and the volume of the static inlet system. Each collection of
extracted gas(ses) obtained by such a method is referred to as an
"aliquot" herein. Thus, for example, the first extraction of a gas
at atmospheric pressure or a different pressure may be referred to
as Aliquot 1, with subsequent aliquot numbers each increasing by
one, so that a three stage analyses will have Aliquot 1, Aliquot 2,
and Aliquot 3. In typical practice, Aliquot 1 is extracted at a
pressure of about 50 millibars. A typical Aliquot 2 is extracted at
an initial pressure of about 5 millibars, and this pressure for a
typical Aliquot 2 is decreased by a period of active pumping
following initial trapping of the more volatile gases to about
0.001 millibars or less (e.g., as low as 0.0001 millibars or lower,
or any range between about 0.001 millibars and 0.0001 millibars,
such as 0.005-0.0005, 0.00075-0.00025, or 0.0009-0.0002 millibars).
The step of causing this significant type of pressure drop in the
system, device, or method of the invention is advantageous in
methods in which a mass spectrometry analysis is performed on the
samples, as mass spectrometry conditions typically require lower
pressures than those in which aliquot extraction methods are
performed in order to appropriately operate. Such pressure
conditions will be known in the art (or provided by the mass
spectrometry manufacturer) and the achievement of such levels of
pressure can be achieved through any suitable means, with many such
methods and devices being available.
[0099] As mentioned elsewhere, the methods of the invention can, in
certain instances, include one or more steps in which potentially
interfering gasses are removed from the released gas or the
environment in which the gas is released. For example, in one
aspect the invention can include the step of flooding the device in
which the method is performed with an inert gas such as argon, so
as to remove gasses from the device, which might provide false
signals or results. Normal atmospheric gasses such as oxygen,
nitrogen, and/or both, for example, can be substantially removed,
or nearly completely removed, or even entirely removed (to
detectable levels) by administering ("flooding") to the device or a
portion of the device in which the method is carried out with such
an inert gas. Such a method also can be used as a method for
refreshing the device between samples. Where an inert gas is used
in such aspects, the inert gas can be any suitable gas that does
not chemically react with the sample and does not cause any
interferences with the chemical analyses of the samples' volatiles.
In other aspects, a non-gaseous material, such as a liquid can be
similarly used. The atmospheric or other interfering gas can be
purged from the device, component, or environment in which the
sample is being analyzed by, e.g., rapid vacuum extraction (e.g.,
applying a vacuum that is sufficiently strong to substantially or
nearly entirely remove the purging inert gas for a duration of
about 1 second or less). In another aspect, the method can comprise
flowing an inert gas through the sample container or area to
displace the potentially interfering gas. Such methods are not
included in every application of the inventive methods. For
example, where the method is performed on samples sealed at a
collection site, such as a well site, such a step is typically not
performed. However, such purging steps can be useful for analyzing
the presence of target substances where such substances are or are
suspected to be present only in very small amounts, such as with
respect to methane and/or helium in samples that are associated
with petroleum production or exploration sites.
[0100] Materials or methods also or alternatively can be used for
removing other potentially interfering substances such as water
vapor, for example, which is relevant to certain aspects of the
invention in which water is formed and analyzed as a method for
analyzing hydrocarbon content in samples. In one aspect, the
invention is performed in the presence of a material that can
capture essentially all, substantially all, or a relevant portion
of the water vapor present around the sample that might be captured
by either the trap or other tools for capturing substances used in
the analytical method. For example, the system that is used for
performing the method can comprise passages between system elements
that are made of stainless steel, which promotes the absorption of
water and thus removes water vapor contained in the gas content
flowing through the system from reaching the next stage of the
system.
[0101] The amount of volatile substances released from the sample,
trapped on the trap, or analyzed by the analytical method of the
inventive methods described herein can constitute any suitable
proportion of the volatiles present in the sample, and the amount
contained at each such stage in each of the aliquots obtained in
multi-aliquot methods of the invention also can be any suitable
amounts. Typically, most of the volatiles are captured by the
method, such that at least about 90%, at least about 95%, at least
about 97%, at least about 99% of the volatiles (excluding water,
and particularly with respect to C1-C10 hydrocarbons and similarly
structured organic compounds) are extracted from the sample, by the
practice of the methods of the invention. The efficiency of the
system typically also is high with respect to trapping of gasses
that are condensable on the trap. Typically, condensable gasses
that can be captured by the trap are not retained in the system in
detectable levels. However, as discussed elsewhere herein certain
gasses will not condense on the trap or otherwise be trapped by the
trap and must be subject to handling by other means to be captured
and analyzed by the method.
[0102] To exemplify (and clarify), methods of the invention can
comprise analysis of a single aliquot, for example a single aliquot
obtained under gentle/low vacuum conditions, or in other aspects
the method can comprise obtaining and analyzing a plurality of
aliquots from one or more samples and/or that are obtained under
different conditions. For example, one method comprises obtaining
two aliquots per sample, wherein the first aliquot is obtained by
application of about 50 millibars (e.g., 10-100 millibars, such as
15-95 millibars, 20-90 millibars, 30-80 millibars, or 40-70
millibars) for about 3 minutes (e.g., 1-10 minutes, such as 1.5-8
minutes, 2-7.5 minutes, 2.5-5 minutes, or the like, in some cases
it may be advantageous to perform the first aliquot extraction for
shorter times in this or other contexts, such as 0.25-4 minutes,
0.33-3.5 minutes, 0.5-3 minutes, 0.5-4 minutes, 0.5-5 minutes,
0.5-2.5 minutes, 0.5-2 minutes, 0.75-3 minutes, 0.75-2.5 minutes,
0.75-2 minutes, or another similar time interval) and a obtaining a
second aliquot by putting the sample under pressure conditions of
about 5 millibars (e.g., about 1-10 millibars, about 2-8 millibars,
about 3-7 millibars, or the like) for a period of about 10 minutes
(such as 5-15 minutes, e.g., 6-12 minutes, 6-10 minutes, 5-9
minutes, 6-9 minutes, 7-9 minutes, 7-10 minutes, or about 7
minutes, about 8 minutes, or about 9 minutes), with the method
optionally including a step of crushing/squeezing the sample during
one or both aliquots, such as crushing the sample at the start of
the first aliquot extraction, as described elsewhere herein. In
some aspects, shorter extraction times (e.g., less than about 5
minutes, less than about 4.5 minutes, less than about 4 minutes,
less than about 3 minutes, less than about 2.5 minutes, less than
about 2 minutes, less than about 1.5 minutes, less than about 1
minute, or even shorter periods. In such aspects the parameters of
the system and the method can be adjusted to facilitate shorter
extraction time, such as, for example, using a relatively larger
diameter needle system for the passage of volatiles out of a
punctured sample container (e.g., use of a needle of about 1/8th or
about 1/16th of an inch internal diameter as compared to about a
32nd of an inch diameter needle). In another approach, extraction
time and/or purging time of the system can be reduced by to passing
a non-condensable purge gas through the sample.
[0103] In some contexts, it may be useful that the method of the
invention is performed and/or the device of the invention is
provided with a plurality of trapping devices, which may be of the
same or different nature. Thus, for example, in one aspect, the
invention includes a plurality of non-selective traps, such as a
plurality of liquid nitrogen traps. This kind of system/device can
be particularly advantageous with multiple aliquot methods. In such
methods it can be possible that each aliquot or at least a subset
of the total number of aliquots are associated with each trap. This
can, among other things, speed up the process of performing
multiple aliquot analyses, for example by exposing the aliquots to
the traps separately or operating traps at different times, such
that there is little downtime in the system in the event a trap
needs to be cleaned, set, or re-set in between uses. Where traps
with different functional properties are provided, using different
traps can enhance the information obtained from the method, by
providing different dimensions to the analysis (e.g., by combining
one or more non-selective traps with one or more selective traps,
such as GC traps).
[0104] As already noted, gasses released from the sample are
released to a system or device in which the remaining steps of the
method are performed. Typically, the gasses pass into the system or
device through an inlet, which may be a portion of the system or
device associated with a needle or flow channel as discussed
elsewhere herein or can be any other suitable type of inlet. Thus,
processes employed before and during vacuum extraction can include
attaching the sample container to the inlet system before
initiation of vacuum extraction and any ancillary processes. A
number of processes can be used to attach the sample container to
the inlet system. These are described in the section on the various
possible configurations of the sample container. Our preferred
sample container is a sealed brass tube with a hermetically
attached nitrile cap on the top and a neoprene plug in the bottom.
Using the typically preferred sample container, the sample
container is attached to the inlet system prior to initiation of
vacuum extraction by passing a needle through the nitrile cap.
Other types of sample containers must be sealed by other
appropriate means to the inlet system prior to initiation of vacuum
extraction.
[0105] Another step of the inventive methods also or alternatively
can include applying energy to either the gasses generated in the
practice of the inventive methods, which can include either gasses
directly released from the sample or gasses that are released from
the trapping device or media of the invention (the "trap", as
further described elsewhere herein). The amount of energy and type
of energy applied to gasses in such aspects can be in any suitable
amount and form so as to generate one or more other target
substances that, for example, are more convenient for detection
and/or analysis than substances that were in the gasses prior to
application of the energy. For example, the methods of the
invention can comprise a step of applying an energy source such as
a source of light energy to a gas, thereby forming compounds from
organic acids, such as carbon monoxide, water, carbon dioxide,
methane, and the like, in amounts that are suitable for detection
by the analytical aspects of the inventive methods. Carbon monoxide
often is preferred as a molecule for detection in that it typically
lacks potential competing signals which may sometimes pose issues
for analyzing water or carbon dioxide. Carbon monoxide is generated
by the breakdown of formic acid (HCOOH) to water (H2O) and carbon
monoxide (CO). This reaction even occurs at about 1 atmosphere
pressures, so much so that some large bottles of formic acid are
provided with a vent that allows carbon monoxide to escape and thus
avoid unwanted pressure build up in the bottle. In contrast, acetic
acid (CH3COOH) breaks down to water (H2O) plus methane (CH4), and
carbonic acid (H2CO3) breaks down to water (H2O) plus carbon
dioxide (CO2). Carbonic acid is only stable in solution, and has no
stable gaseous phase.
[0106] The amounts of organic acids released from materials, such
as cuttings, may be very small, and their respective indicator
break down compounds may be masked by larger amounts of these
compounds being released as compounds existing as those compounds
in the sample. In geologic samples this is especially true for
water, carbon dioxide, and methane. This is not a usual problem for
carbon monoxide as its natural occurrence in samples from oil and
gas wells is minimal at best. However, carbon monoxide can be
generated as a by-product of oil and gas drilling by the process
known as "bit burn" or "drill bit metamorphism.sup.-. In a lab
apparatus aspect of the invention, and related methods of use, some
of the compounds derived from organic acids that are also present
as naturally occurring interfering compounds, such as water and
carbon dioxide, are frozen to a liquid nitrogen (LN2) trap. Carbon
monoxide and methane do not freeze to the LN2 trap. However,
methane as a naturally occurring substance is common in rocks from
oil and gas wells. Therefore, the presence and amount of methane in
rocks from oil and gas wells is not an adequate indicator of
precursor organic acids. Carbon monoxide is not at all common as a
natural component of rocks from oil and gas wells. Therefore, the
presence of carbon monoxide typically is a good indicator of
organic acids. Thus, for example, in one set of aspects the
inventive methods comprise detection of carbon monoxide, but not
methane or at least do not comprise relating methane levels to
overall levels of organic acids in the material associated with the
sample/cuttings.
[0107] In certain aspects, carbon monoxide is monitored using the
AMU12 fragment formed by mass spectrometry analysis of carbon
monoxide. In a more particular aspect, the method comprises
performing a method in which carbon monoxide is a primary indicator
of organic acids in the material, and is analyzed by evaluating the
presence and amount of the AMU12 fragment formed by mass
spectrometry performed on carbon monoxide, and the method is
performed either free of any detectable amount of carbon dioxide or
in the presence of an amount of carbon monoxide that does not
result in a distortion of the carbon monoxide-associated AMU12
signal or the degree of the AMU12 signal that is associated with
carbon monoxide. In some aspects, the amount of interference with
the AMU12 signal from the presence of carbon dioxide in such a
method is less than 25%, less than 20%, less than 15%, less than
10%, less than 5%, less than 2%, or less than 1%. In settings where
carbon dioxide is present, the method can comprise either manually
or automatically correcting the AMU12 signal data for the presence
of carbon dioxide to obtain a carbon monoxide-associated AMU12
signal. In some aspects, the step of isolating carbon dioxide is
handled by use of a trap that collects carbon dioxide, such as a
liquid nitrogen trap, in a manner such that carbon monoxide and
carbon dioxide are not in associated aliquots (for example, carbon
monoxide in a lab device of the invention may be collected in a
non-condensable gas state, whereas carbon dioxide is fixed to the
liquid nitrogen trap). In other aspects the method of analyzing
carbon monoxide level also or alternatively comprises analyzing the
signal from AMU13 and/or AMU 16 and/or 28. In aspects where carbon
dioxide is initially present but removed or substantially removed
(e.g., by removal of at least 85%, at least 90%, at least 95%, at
least 97%, at least 99%, or more, of the initial concentration) as
a part of the inventive method, a CO2 absorber, such as
Decarbite.TM., also or alternatively can be used to reduce or
eliminate any detectable levels of carbon monoxide in the gas or
aliquot to be analyzed, Also or alternatively, a mass spectrometer
based machine designed to detect trace amounts of carbon monoxide
in cuttings can be designed to use any of the CO2
eliminating/reduction techniques described herein and their known
equivalents in the art.
[0108] In another aspect, the method is performed under conditions
in which the application of the energy also or alternative changes
the pressure of gas associated with the sample or generated from
the sample in a manner or amount that is indicative of a chemical
change that identifies the presence of a target substance or a
target-related substance (such as carbon monoxide).
[0109] It is important to note that while in many aspects of the
inventive methods mass spectrometry analysis is an important
component of the inventive method, such a step is not always
included (and often is not included) in these methods. Rather,
other analytical steps can be performed to identify the presence of
the target substance or target-related substance. For example, a
carbon monoxide meter or measuring device can be used to directly
measure the formation of carbon monoxide in a petroleum-related
sample, thereby indicating the presence of organic acids prior to
application of the energy, and thereby further indicating the
presence of oil-related substances in the sample (and material).
Also or alternatively, simply measuring the pressure in the gas
related to the sample can be indicative of a relevant change, such
that a pressure gauge, meter, or device can be used in the method,
alone or in combination with mass spectrometry analysis (carbon
monoxide monitoring also can be combined with mass spectrometry
analysis or all three methods can be combined in the analytical
method).
[0110] Such methods of the invention also can often be desirably
performed in the field, such as directly at a well or exploration
site. Accordingly, whereas many aspects of the invention comprise
the use of small samples, in these and other methods larger amounts
of materials may be used, such as cup sized containers, pint size
containers, quart size containers, gallon size containers, or
containers that have volumes of about 5 liters or more, about 10
liters or more, about 20 liters or more, or even about 30, 40, or
50 liters or more (e.g., a large bucket of sample material). For
example, a large container of cuttings can be collected from where
cuttings are deposited near a well site (e.g., in association with
a well site shaker table) and then directly used for analysis with
such methods.
[0111] In addition to or alternatively to light energy, other
suitable types of energy can be applied to the sample in order to
modify the gas content for direct evaluation or to see if pressure
increases, indicating a change in content that is indicative of the
presence of the target substance in the material. Examples of other
types of suitable energy include heating methods, vacuum, other
forms of radiation (e.g., UV light), and the like. In another
aspect, the method also or alternatively can comprise performing a
chemical reaction to form such compounds that are indicative of the
presence of the target substance in the material. The amount of
energy applied in practice of the method can be any suitable amount
to achieve the desired change. In one exemplary aspect, the sample
is heated to about 400 degrees C. or greater for a period
sufficient to generate indicative target compounds (e.g., carbon
monoxide) from organic acids present in the samples.
[0112] Methods of the invention can and often do include the step
of subjecting a sample of the material, such as one or more
cuttings associated with one or more geologic formations, to one or
more forces to cause the release of a first gas containing an
analyzable amount of one or more volatile substances. The force
that can be applied to the sample can include a pressure force,
such as a high pressure (positive pressure) or a vacuum;
temperature; chemical reaction; application of radiation (such as
microwave, which might be used to remove water from material);
and/or physical forces, such as crushing or vibration (e.g.,
ultrasonic vibration). Other forces that can be applied include
dehydrating the sample by heat or chemical means, applying
temperature to the sample, applying mechanical pressure on the
sample, mechanically rupturing some or all the sample, subjecting
the sample to a chemical reaction, or a combination of any or all
thereof, optionally in addition to applying one or more levels of
vacuum and/or pressure to the sample.
[0113] In one aspect, the force is a vacuum pressure, such as the
vacuum pressures described above. For example, a low pressure can
be applied to a sample of the material as a means for causing one
or more volatile substances to be detectably released from the
material (or a vacuum can be applied that would increase the
release of one or more volatile substances or gas(ses) from the
sample if such a volatile substance is present). The precise amount
of vacuum will vary depending on the material and other conditions
of the method. Commonly the pressure will be below atmospheric
pressure but greater than about 3.times.10-4 millibars. In another
aspect, practicing a method of the invention comprises applying a
vacuum to the sample at a pressure that is between atmospheric
pressure and about 1.times.10-3 millibars. In yet another aspect,
the method comprises applying a vacuum to the sample at a pressure
that is between atmospheric pressure and about 25.times.10-3
millibars. In still another facet, practicing a method of the
invention comprises applying a vacuum to the sample at a pressure
that is between atmospheric pressure and about 1.times.10-3
millibars. In yet another aspect, the method comprises applying a
vacuum to the sample at a pressure that is between atmospheric
pressure and about 1.times.10-2 millibars. In still another sense,
methods of the invention can comprise a step of applying a vacuum
to the sample that is defined by a pressure of between about 1 to
about 100 millibars.
[0114] In other particular aspects, the method comprises applying a
positive pressure to the sample. A positive pressure can be any
pressure that is in excess of ambient atmospheric pressure and that
results in a measurable release of desired gas(ses) (at least under
conditions in which volatile substances that form such gas(ses) are
present in the sample). Positive pressure can be applied by any
suitable means, such as, for example, using a piston. The method
can include one or more applications of positive pressure, or the
combination of application of positive pressure with any of the
other methods described herein for aiding disrupting the sample
and/or extracting fluids from the sample. The specific pressure
applied will depend on the other conditions of the method, such as
the nature of the material and whether other forces are applied to
the sample. In one example, a pressure of about 400 to about 4000
pounds is exerted on the sample (e.g., about 1000 pounds to about
3500 pounds), although higher pressures also can be exerted by
using certain methods available in the art, such as hydraulic
pistons.
[0115] In another aspect, the method also or alternatively includes
application of a physical force, such as crushing, abrasion,
thermal decrepitation, grinding, and/or drilling. For example,
materials can be loaded into a sample container comprising a
crushable portion, such as a crushable sidewall, and the sample
container can be subjected to crushing so as to promote the release
of volatile materials. For example, as discussed elsewhere herein,
samples that are or that comprise cuttings can include hydrocarbon
materials contained in small fissures, pores, and other structures,
which are distinguishable from fluid inclusions, by their exposure
to the environment and/or in that they are characterized in not
being hermetically sealed in an inclusion. These formations in
geological material, which are also represented in cuttings taken
from such material, can contain hydrocarbons, such as
petroleum-related hydrocarbons, which are held in the geologic
material. Application of a physical force, such as crushing, can
assist in releasing such materials from such formations. Selection
of the parameters for these methods will vary with the nature of
the material, other parts of the analytical method, etc. A typical
exemplary method of the invention will comprise crushing samples,
such as cuttings, by about 400 pounds to about 4000 pounds, which
can be achieved using some of the exemplary devices described
herein.
[0116] It should be noted that in certain aspects of the invention
no force is applied to the sample. In other words, just the
exposure of the material to a release channel, such as a needle
that penetrates a container in which a sample of the material is
contained, can allow the gas to be exposed for performance of the
next step of the method or to flow to either another container,
portion of a device of the invention, or the like, wherein such
other steps can be performed. For example, in one aspect, the gas
that is released from the sample will flow to a gas trap device,
such as a liquid nitrogen gas trap, such that a portion of the gas
becomes trapped in the trap and thereafter can be released in a
predictable manner.
[0117] In one embodiment, methods of the invention are
characterized by the collection of the sample in a sealed container
and by the subjecting the sample for an initial period to
approximately the same pressure (e.g., within 90%, 95%, 99%, or
more of the same condition) or exactly the same pressure (at least
within limits of detection and/or condition, such as at atmospheric
pressure without respect to natural fluctuations in such pressure)
at which the sample was sealed in the sample container, such that a
majority of the volatile materials are not lost when released from
the container. Often this means that the sample will initially be
subjected to atmospheric pressure.
[0118] In another aspect, in addition or alternative to crushing
the sample, by the methods described elsewhere herein the methods
can comprise mechanically rupturing some or all of the sample,
subjecting the sample to a chemical reaction, or performing a
combination of any thereof, alone or in combination with
application of crushing, compression, or the like. In another facet
of the invention it is characterized by the lack of any step that
comprises application of heat (e.g., an increase of temperature of
about 25% or more, about 35% or more, about 50% or more, about 75%
or more, about 100% or more, etc.) for a period of more than about
12 hours, such as more than about 6 hours, more than about 4 hours,
or more than about 2 hours.
[0119] In one aspect of the invention the method comprises
isolating or "trapping" some portion of the gas released from the
sample by contacting the released gas with a "gas trap" (which may
also simply be called "a trap").
[0120] "Trapping" means that the trapped gas is collected and
maintained or held in a device, medium, and/or location. Trapping
in the context of these aspects of the invention typically occurs
in a releasable manner, and commonly the gas is trapped in a manner
such that parts of the trapped gas can be released from the trap in
a predictable manner, such as when some kind of change is made to
the condition of the trap. For example, in one aspect the trap is a
material that bonds to some portion of the gas and the gas is
released by changing the conditions of the bonding, for example, by
increasing the temperature.
[0121] In a preferred aspect, the trap is a cryogenic trap, such as
a liquid nitrogen trap, which traps gasses through freezing of
volatile compounds onto a surface that has been cooled by liquid
nitrogen or other cryogenic methods thereby freezing the volatile
compound to the trap device or trap media. In such embodiments, the
method can include the step of releasing of volatile compounds from
the trap due to warming of the trap, thereby releasing volatile
compounds from the trap in a predictable sequence for further
analysis and/or treatment. Freezing traps can be operated under any
suitable conditions. Typically, conditions will be selected based
on the properties of the material to be trapped by the media or
device used in the inventive method. In one aspect, the trap is a
material or device that is cooled to about minus 50 degrees C. or
less in the performance of the method (e.g., about minus 100
degrees C. or less, such as about minus 150 degrees C. or less,
such as about minus 190-200 degrees C., although in some cases
colder temperatures can be obtained and employed). Commonly, the
cryogenic trap will be cooled to such a temperature prior to the
exposure of the gas released from the sample to the trap. In this
respect, as in some of the preferred devices described below for
practicing the inventive methods, there may be one or more
controllable valves that are used to controllably expose the
sample-release gas to the trap, and the method correspondingly will
include the step of exposing the trap to the sample-release gas in
a controllable manner, after such cryogenic cooling.
[0122] Other types of traps may also be suitable for performing
steps of the inventive methods. In one case the trap may be
selective, in that it is either capable (or more capable) of
selectively binding to certain materials and/or selectively not
binding certain materials. In one case, for example, the trap is
selected such that it is selective for not trapping water, carbon
dioxide (or other compounds that might interfere with parts of the
analysis, make analysis more difficult and/or less accurate),
and/or make analysis take longer or cost more) and/or one or more
organic acids, particularly if analysis of the organic acids is
also a part of the method.
[0123] Typically, however, the trap used in the inventive method is
a non-selective trap, at least with respect to target substances of
interest. The term "non-selective trap" in the context of this
invention typically means that the trap binds to all or
substantially all of the volatile compounds present in the sample
or all of the relevant volatile compounds that are present in the
sample. The operation of such a non-selective trap can be
contrasted with a selective trap, such as may be found in a gas
chromatograph ("GC"), which binds to a certain compound or a class
of compounds, but does not bind to other compounds. This is not to
exclude application of GC technology in performing certain aspects
of the invention, as aspects of the invention in which GC
technology is used are described elsewhere herein and, as noted
above, in certain cases selective traps, such as using a GC
material (or set of such materials), could be part of a trap
component of the invention, or could constitute the trap.
[0124] In aspects where the gas is subject to a trap, the material
contained in or that is otherwise bound to the trap can be
considered to form an "aliquot" that is used for further analysis
according to various aspects of the invention.
[0125] As noted above, gas trapping devices, media, or systems,
which can be used in various contexts of the invention, can be
either selective or non-selective. In one aspect, the gas trapping
device is a non-selective trap, capable of capturing gas containing
a number of different types of volatile compounds, such as a
cryogenic trap which freezes volatile compounds to fix them to a
media. A liquid nitrogen trap is an example of such a cryogenic
trap.
[0126] The gas released from the sample (or "first gas") will be
allowed to contact the trap for any suitable period of time. The
optimal time of contact will vary with the trap, the gasses that
are present or expected to be present, and other factors. For
cryogenic traps, such as the liquid nitrogen trap described above,
the time of contact between the trap and the volatile substances
can be relatively short, such as less than about a minute, and
commonly less than about 45 seconds, usually less than about 30
seconds, and often as little as about 15 seconds, about 10 seconds,
or less than about 10 seconds (such as 7, 6, or even 5 seconds)
will be suitable. In certain cases, the trap will comprise a
pumping function, such as in the case where the trap is a cryogenic
trap/pump, which may occur by the action of freezing substances to
the trap. In this respect, having conditions that cause freezing
quickly can be important, as such quick freezing removes volatile
compounds from the atmosphere surrounding the sample, which will,
in turn, cause more volatile compounds to be released from the
sample (as the system works towards equilibrium).
[0127] However, the entire period that gasses released from the
sample are exposed to the trap will be significantly longer than
these short periods, such as a period of about 10 minutes or
longer, for example about 15 minutes or longer, about 20 minutes or
longer, about 30 minutes or longer, about 40 minutes or longer, or
about 60 minutes or longer. The amount of time of exposure depends
on the pressure applied, the nature of the sample, and other
factors. When, for example, seeking to release and analyze more
refractory substance in the sample and/or when dealing with a
particularly difficult sample material, longer times of application
may be required, such as about 15 to about 30 minutes. However, in
other aspects, the amount of time that is applied is about 10
minutes or less, such as about 8 minutes or less, about 6 minutes
or less, or even about 5 minutes or less.
[0128] In some cases, where the method is performed with repeated
cycles, the cycles can vary in terms of the amount of time in which
gas is exposed to the trap. For example, in the first cycle of a
method the time may be relatively shorter, such as less than about
10 minutes, where there may be more gas readily available in
association with the cycle, whereas in subsequent cycles, where it
is more difficult to extract gas from the sample, a longer period
of time may be employed, such as about 10 minutes or longer, so as
to permit the second cycle gasses to sufficiently bind to the
trap.
[0129] In aspects in which an extended time prior to the warming of
the liquid nitrogen trap is provided, the extended time is not
solely to provide more time for the gasses to bind to the liquid
nitrogen trap, but, rather, such an extended time can provide for
improved extraction or liberation of volatile species from the
sample. Thus, the liberation of volatile gasses from a sample can
be, at least in some respects, considered to depend on the
variables of the nature of the sample, the nature of the volatiles,
the forces applied on the sample to promote release of such
volatiles, and the time given to permit such release and/or
collection of gasses. It is often preferred that all volatile
fluids that are gaseous in the sample are collected prior to
exposure to any vacuum. Where the sample contains volatile liquids,
the application of vacuum to the sample, such as after "passive"
(non-vacuum) collection of gaseous volatile substances from the
sample, can be desired, inasmuch as such application of vacuum may
lead to boiling of substantially all or all of such liquids, or at
least result in the boiling of a substantial proportion of such
volatile substances (at least 20%, at least 30%, or at least 33% of
the amount); a majority of the substances; a substantial majority
of the substances (at least 66.66%, at least 75%, at least 90%, at
least 95%, at least 99%); or at least a detectable amount of such
substances. In any case, the boiling of such volatiles that are
normally liquid (at atmospheric pressure and typical ambient
temperature) will render such boiled substances or boiled fraction
of such substances gaseous. The length of time required to achieve
a desired level of boiling of liquid substances in the sample is
dependent on factors similar to those described above with respect
to release of gaseous volatile compounds, but will primarily depend
on the weight of the substance (heavier materials typically require
longer to boil). Application of longer periods of vacuum, and
resultant boiling, can, thus, result in the conversion of a
significant amount of liquid volatiles into gaseous species for
analysis in accordance with the inventive methods described herein.
Thus, the certain aspects of the invention that comprise
application of extended periods of time for release of gaseous
volatile substances from a sample and/or application of vacuum to
boil liquid volatile compounds in a sample provide the inventive
methods a unique advantage over the prior art in that more of the
volatile substances in a sample can be fully analyzed by allowing
the time required for more of the volatile liquids to be released
and/or captured.
[0130] In one aspect of the method, the change in temperature used
to release gas species from the liquid nitrogen trap is performed
in less time than flash warming methods used in gas chromatograph
(GC) methods that also use liquid nitrogen trapping. Such GC
methods use "flash" or rapid warming applied to a liquid nitrogen
trap used in the GC method, which release many, most, or
substantially all of the gasses trapped to the liquid nitrogen trap
at once. GC methods also require that all of the gasses to be
analyzed enter the GC media simultaneously, such as a trap if used
in the method, nearly simultaneously, as the presence of all of the
gasses to be analyzed at the same time is necessary for the
effective performance of such analytical methods. These limitations
are typically not required (or desired) for the inventive methods
described herein, and as described elsewhere a gradual warming of
the liquid nitrogen trap over a more sustained period of time to
permit for the predictable release of trapped gasses is a common
aspect of methods of the invention that comprise a trap, such as a
liquid nitrogen trap. Also, this negates the need for any kind of
separation of gasses other than the warming of the liquid nitrogen
trap in these aspects of the invention. Thus, in another facet of
the invention, the invention lacks any step of molecular selection,
such as molecular distillation or similar method, being performed
on the substances to be analyzed in the method.
[0131] In some aspects, a relatively high vacuum can be applied to
a trap or applied in the device or system used to carry out the
inventive method such that the trap is under vacuum conditions for
a period of time. For example, in some cases where a relatively
high vacuum is applied to a sample that vacuum also may be applied
through other parts of the system, including the trap. In other
aspects, the method also or alternatively comprises a method in
which vacuum is applied to capture non-condensable gasses and
remove such material from contact with the trap (or to at least
substantially achieve such a state).
[0132] In certain aspects, such as where relatively high vacuum is
applied to the trap or in the system such that a vacuum condition
is present at the trap for a period, it can be advantageous to
continue to reinforce the trap media or device with whatever
substance is used to trap the target gasses, such that gasses that
might be easily/readily released from the trap are maintained in
contact with the trap. For example, in the case of a liquid
nitrogen trap the method can comprise continuously applying liquid
nitrogen to the trap while the vacuum condition is present so as to
retain substance of interest (e.g., ethane, ethene, etc.) trapped
into the trap until they are ready for release in a predictable
manner.
[0133] Another action that can form part of the methods of the
invention is the step of isolating the aliquot from the sample.
Commonly, once gasses are collected from the sample to form an
aliquot, that aliquot can then be isolated from the sample, such
that the remainder of the analysis of the method or at least that
step or part of the method is conducted on the aliquot without
further collection of gas from the sample for the collection of the
present aliquot (or if this is the final aliquot or only a single
aliquot is being collected for the particular application of the
method). This method of isolating can be performed for many reasons
and using any suitable technique. Where devices of the invention
described elsewhere herein are used in the practice of the method,
for example, one or more valves may be engaged, which results in
isolating the gas of the aliquot from the sample. The method also
or alternatively can include the step of isolating the trapped
gasses from access to other components of the device or system in
which the trap is situated. For example, where the method is
performed with a device of the invention that comprises (a) a
sample holding unit, (b) a gas trap, and (c) a mass spectrometer,
the method typically will comprise the step of isolating the gas
trap from both the sample holding unit and the mass spectrometer
for one or more periods of time (e.g., isolating the trap from the
samples after a sufficient passage of time and/or application of
conditions necessary to collect gasses from the sample and
isolating the mass spectrometer until it is time to release the
gasses from the trap to it for analysis).
[0134] In aspects of the invention in which one or more gasses
released from the sample are subjected to a trap to form an
aliquot, the method typically includes the step of releasing
volatile substances from the aliquot as trap-released gasses in a
predictable sequence. For example, where the sample is comprised of
one or more drill cuttings obtained from an oil well site, gas is
obtained from cuttings, either passively or by the application of
one or more forces, such as mechanical crushing and/or application
of one or more vacuum pressures on the sample, and then subjected
to a trap, such as a liquid nitrogen trap. Much of the gas from the
cutting samples will be captured by the trap. Allowing the trap to
heat, either passively, or, more typically through the application
of heat, directly or indirectly, to the trap, will allow for
volatile substances in the gas that are frozen to the trap to be
released in a predictable manner.
[0135] A "predictable manner" means that substances such as
individual volatile gasses or mixtures or other types of volatile
gas species are released from the trap in a manner such that if
gasses are present their release can be predicted from the timing
and/or condition of their release. For example, in one aspect a
predictable manner means that different species are released as a
function of time. In many aspects, the release of species can
overlap the release of other species, such that, for example, there
may be first period of release of one or more first species (e.g.,
lighter or more volatile compounds), a second period in which there
is a release of one or more second species (e.g., heavier or less
volatile compounds), and an intervening period in which both the
one or more first species and one or more second species are both
being released. In many aspects, there will be several such periods
and intervening periods. The periods and intervening periods may,
however, form a predictable pattern of release such that if
expected compounds are present in the sample it will be known to
expect them to release at a certain time and/or under the
application of a certain condition.
[0136] Another step of the inventive methods also or alternatively
analyzing gasses that are directly released from samples, typically
after the application of an energy to the gas, to break down
(decompose) substances in the gas, thereby turning volatile species
in the gas to target substances for analysis. For example, such a
method of the invention can comprise taking a volume of a sample,
such as cuttings, optionally applying one or more forces to the
sample so as to release one or more endogenous volatile gasses
(such as formic acid, acetic acid, carbonic acid; or other organic
acid), applying an energy source to volatile gasses so as to break
down the volatile species to one or more target compounds (such as
carbon monoxide), and analyzing the target compounds to determine
whether the endogenous volatile substances were present,
particularly if the presence of such endogenous substances are
indicative of the presence of petroleum or another material that is
desired. In such methods, optionally no trapping of a gas is
performed and/or no mass spectrometry or similar method is applied.
This aspect of the invention provides simple methods that can be
readily performed with limited amounts of equipment, while still
providing a sufficient indicator that petroleum or another target
substance is in the relevant formation associated with the
sample.
[0137] The amount of energy to be applied can be any suitable
amount of energy and/or force to break down the volatile substances
into the target substances. In one aspect, the invention comprises
applying heat of about 400 degrees C. or higher or another
temperature or condition so as to disassociate formic acid,
carbonic acid, or both (in one aspect, carbonic acid only) to one
or more components thereof, such as carbon monoxide and/or carbon
dioxide. In another aspect, the method comprises applying a vacuum
to the sample to assist or handle the breakdown of the endogenous
volatile substances into the target gas(ses). Vacuum conditions
described elsewhere herein have been associated with such breakdown
of endogenous gasses and may be applied in this aspect as well. In
still another aspect, the invention also or alternatively comprises
contacting the sample with one or more chemicals that assist in the
release of the target gasses from the endogenous gasses, such as
application of a desiccant. Another aspect comprises application of
radiation, such as microwaves, to the sample, to aid with the
breakdown of the endogenous gasses.
[0138] The methods of the invention also include the step of
analyzing gasses generated or released in the various methods
(e.g., trap-released gasses or decomposed gasses generated where no
trapping is performed), so as to determine if substances of
interest are present in the formation or material from which the
sample was taken or with which the sample was associated. Any
suitable type of analysis can be applied to such gasses and any
suitable combination of methods can be applied as well, if desired
and possible.
[0139] A preferred aspect of the inventive methods described herein
comprises the application of mass spectrometry analysis to
trap-released gasses. Any suitable type of mass spectrometry method
can be used in this respect.
[0140] When performed in the practice of the invention, a mass
spectrometry method typically will be selected to be suitable for
the identification of expected or desired target substances. For
example, if the desired task is to identify the presence of
petroleum-relevant hydrocarbons and/or organic acids and/or
inorganic gasses (e.g., H.sub.2S, helium, and CO.sub.2) in cuttings
obtained from an oil well, the mass spectrometer will be selected
and operated such that it can identify, among other things,
volatile gasses such as octanes, nonanes, and larger hydrocarbons
that are indicative of the presence of petroleum in the geological
formation from which the cuttings originated. Mass spectrometry is
typically a preferred method as it works rapidly and provides a
useful, detailed level of analysis. There are a variety of mass
spectrometry devices that can be used in performing methods
involving mass spectrometry. A quadrupole mass spectrometer
(residual gas analyzers (RGAs)), for example, are readily available
devices, which might be suitable for many of the methods described
herein. Time of flight mass spectrometers, which provide rapid
analysis, also may be suitable in many instances. More complex
systems, such as mass spec/mass spec (dual mass
spectrometers/triple quads) also could be used in some cases and
may be advantageous for better resolving substances with masses
that are similar to other substances which may be present.
[0141] Mass spectrometry is not a required component of the
invention, however, as other analytical methods can be used to
analyze samples in accordance with the invention. Flame Ionization
Detection could be used for analysis of various hydrocarbon
species. Gas chromatography also or alternatively can be used to
analyze gasses in certain aspects of the invention. It also or
alternatively may be possible to analyze hydrocarbons via infrared
spectroscopy or Raman spectroscopy.
[0142] Other times simpler methods can be used in the place of mass
spectrometry or such sophisticated methods, such as gas
chromatography. In important aspects of the invention the invention
comprises detecting the formation of target substances which are
released from organic acids, such as carbon dioxide or carbon
monoxide, which can be detected using conventional, commercially
available detection devices or the technology in such devices.
Pressure release, for example, may also or alternatively be used as
an indicator in some methods. Water release could simply be
measured using a humidity meter, and also or alternatively provide
relevant information in certain aspects of the invention.
[0143] Although the methods of the invention can be performed with
various approaches, in some aspects methods can be characterized by
steps that are not performed and/or the components that are absent
from a device or system of the invention. For example, one aspect
of the invention is characterized by the lack of any gas
chromatography step in the method (or, correspondingly, by the lack
of such device/component in the system/device of the invention).
Other steps that may be excluded from the methods of the invention
include infrared analysis. It will be understood that generally the
principles described herein with respect to the methods of the
invention will implicitly carry over to the devices and systems of
the invention, such that this description should also be
interpreted as disclosing devices and systems lacking infrared
capabilities.
[0144] In aspects of the invention where a trap is used, another
optional step of the inventive method is collection and analysis of
non-condensable gasses (i.e., gasses that will not condense and
securely bind to the trap, and/or other materials from the sample)
("NCGs"). In some aspects, application of one or more other steps
of the method may generate materials that will not bind to the gas
trap. For example, where a liquid nitrogen gas trap is used some
materials may not be too volatile and/or some gasses may not bind
the trap or at least not bind to the trap completely or bind to the
trap in sufficient quantities to indicate an accurate amount of the
material or even to indicate the presence of the material at all in
the sample. In such cases the method can include collecting
non-condensable materials and/or non-binding gasses. These
materials may be collected, such as by applying a collection method
to isolate such material for later analysis. In the use of devices
of the invention, the device can include a mechanism for collecting
such materials in a manner that isolates them from the rest of the
material to be analyzed. A vacuum can be applied to gasses that are
not bound by a trap, for example, to collect such gasses. Ideally
such gasses are isolated and captured in a container or structure
functioning as a container in a device and then selectively
subjected to analysis before or after analysis of the trapped
gasses. In some aspects, the NCG material may be in too great a
quantity for analysis and the method will comprise a step of
limiting the amount of NCG material that is analyzed and/or
controlling the rate of analysis of the NCG material.
[0145] In some aspects, the methods of the invention can include
the step of repeating various steps of the method. For example, in
one aspect the invention provides methods comprising a cycle of
repeatedly applying one or more forces to the sample to cause or
assist in the release of volatile compounds from the sample. Such
methods can include the repeated application of the same type of
force or applications of two or more different forces or the
application of the same type of force but in a different amount,
duration, etc. For example, in one aspect the invention provides
methods in which vacuum is applied to the sample several times, at
different pressures, for different periods, or both. In some
aspects, gasses expected to contain certain volatiles under this
condition are the target of one or more analytical methods
practiced on the gasses or on trapped gasses generated from the
sample-released gasses. Such methods typically also will include
multiple steps of capturing the multiple gas aliquots generated by
application of the multiple forces, releasing such respective
gasses, and analyzing such released gasses, which can then be
examined in combination to obtain a profile for the sample.
[0146] Analysis of substances by the methods of the invention can
be qualitative (determining the presence, but not the amount),
quantitative, or both. Methods of the invention in which trapping
and predictable release of trapped gasses occur are particularly
amenable to quantification. In one aspect, the invention provides a
method that is capable of quantifying the amount of one or more
volatile compounds contained in the sample. Quantification can be
performed through analysis against a standard. For example, a
standard of a gas at a known volume and known pressure can be
generated and a sample can be compared to this standard. Similarly,
a drop of a liquid of known volume and composition can be analyzed
by the method employed and then the result(s) from the sample(s)
compared to such a standard. Standard compositions are typically
comprised of a NCG, such as nitrogen (e.g., at least about 80% is
nitrogen or at least about 85%, at least about 90%, or more of the
standard is nitrogen and/or methane), with the small remaining
amount comprising a known amount of one or more hydrocarbons, which
will be released from the trap at different temperatures, and
allowing for quick analysis of the standard material. Because
standards may not be contained in a material such a cutting the
method may comprise controlling the volume and/or rate of release
of material analyzed (e.g., by using a needle or constricting
passageway to control the flow of the sample material to the
analytical components of the system).
[0147] Methods of the invention can comprise analyzing the sample
for the presence of organic acids and/or hydrocarbons, with the
analysis of the presence of organic acids (which typically is done
by analyzing for the presence of other target substances, such as
carbon monoxide, which indicate such organic acids are present)
typically being preferred or selected if only one of the two are
analyzed. Nonetheless, the analysis of hydrocarbons also can be
important. For example, analysis of C5-C10 hydrocarbons in the
sample can provide information about the entire volume of petroleum
in a formation, once the presence of petroleum is established by
identifying target substances that indicate the presence of
petroleum-associated organic acids (e.g., formic acid and/or
carbonic acid, or only carbonic acid). Where samples sealed at the
well or other collection site are analyzed in the method of the
invention, hydrocarbon data can directly correspond to the presence
of oil in the associated formation. In the case of old, non-sealed
samples, hydrocarbons are likely to be associated with fluid
inclusions only, and the presence of hydrocarbons alone in such
materials may not be sufficient to accurately identify the presence
of petroleum in the formation in question.
[0148] In one aspect, the analytical method comprises analyzing the
amount of water in the analyzed gasses (e.g., the trap-released gas
in a method in which gasses are trapped and released). I have
surprisingly discovered that high water concentration (in geologic
material and/or in a sample of such material) can be indicator of
oil saturation. While not wishing to be bound by any particular
theory, I believe that one or more organic acids, such as carbonic
acid, formic acid, and/or acetic acid, which is/are present in
cuttings or samples will break down in the performance of certain
aspects of the inventive method thereby generating more water than
would ordinarily be present in the sample (e.g., from analysis of
such cuttings by extraction of gas therefrom containing volatile
compounds, capturing such gasses on a liquid nitrogen trap,
releasing such gasses from the liquid nitrogen trap in a
predictable manner, such as through accelerated warming of the
liquid nitrogen trap, and subjecting the released gasses to mass
spectrometry analysis). However, in other aspects of the invention,
other compounds than water are also or alternatively analyzed to
assess the sample. This is particularly true as other organic acids
associated with samples may not release water.
[0149] In one aspect of the invention, detection of excess water
associated with a sample as an indication of petroleum-associated
hydrocarbons is made under conditions in which petroleum
compound-associated excess water in the sample can be detected and
distinguished from other water in the environment. For example, in
aspects of the invention in which a liquid nitrogen trap is used in
the method and/or incorporated into the device/system of the
invention, the observation of water at temperatures below that
which normal water release is expected. Thus, for example, in one
aspect the method comprises the detection of water at a temperature
that is significantly colder than -55 degrees C. (a temperature
representing about the lowest temperature at which water would
typically be expected to be released and detected), such as a
temperature of about -70 degrees C. or less (colder), about -80
degrees C. or less, about -100 degrees C. or less, about -110
degrees C. or less, about -120 degrees C. or less, or even cold
temperatures, such as about -130 degrees C. or even about -140
degrees C. (e.g., about -100 degrees C. to about -200 degrees C.,
such as about -120 degrees C. to about -180 degrees C.). In
experiments conducted with systems of the invention, such as the
system exemplified in FIG. 1, water can be detected when released
at temperatures of about -140 degrees C. (a temperature normally
associated with a carbon dioxide peak/release) and at higher
temperatures (present in the system when the system is allowed to
warm or is warmed by the application of heat from heaters in or on
the system), but above -55 degrees C. Typically, the detection of
water by a mass spectrometry system will occur in a plurality of
distinct peaks associated with such temperature increases, ranging
from about -140 degrees C. to about -55 degrees C. in such a
system/device. Without being bound by theory, it is believed that
the detection of water under such abnormally cold conditions
reflects the breakdown of organic acid compounds during or after
release from the trap and/or from water generated by acid
decomposition by ion fragmentation resulting from electron
bombardment under high vacuum in the mass spectrometer. In any
event, the detection of water under such cold conditions,
especially when combined with conditions that would lead to and/or
permit the decomposition of organic acids associated with samples,
such as petroleum well-associated cuttings, is another important
aspect of the invention.
[0150] In particular aspects, if the water evolution (generation)
caused by acid decomposition occurs during, or after, acid release
from the liquid nitrogen trap then some of the water, but typically
less than all of the water, created by acid decomposition may be
re-trapped on the LN2 trap, but the remainder of that newly formed
water escapes the trap and is analyzed. Other noncondensable gasses
that form from the acids' decompositions, e.g., methane from acetic
acid and carbon monoxide from formic acid, typically are not
trapped back onto the trap, but are usually transported and
analyzed in the mass spectrometer upon the acid's evolution from
the trap.
[0151] The separation of water evolved from acid breakdown from
normal water via evolution from a trap, for example a cryogenic
trap such as a liquid nitrogen trap, has not been previously
described by others, and this phenomenon is a unique advantage of
this invention. As discussed herein mapping of oil and gas
associated acids using water and other indicator compounds is a
unique feature of this invention and has many applications for oil
and gas exploration and production.
[0152] In yet another aspect, the method comprises a
P.sub.2O.sub.5-based analysis of the water content of one or more
samples analyzed in the method. Gas from a sample (typically after
heating to drive water off the rock before release of the gas) can
be transferred around/over a P.sub.2O.sub.5-containing apparatus or
container (with a known weight) and the weight thereafter measured
to determine the amount of water present in the sample. Such
methods can be advantageously performed on water in fluid
inclusions as part of the inventive method, as water can be
difficult to analyze in the context of analyzing fluid
inclusions.
[0153] In one aspect, the method includes using
hydrocarbon-containing fluid inclusions as a negative indicator of
the presence of oil. In certain aspects the presence of
hydrocarbon-containing fluid inclusions is a negative indicator of
the presence of oil in a material and the presence of a low number
of hydrocarbon-containing fluid inclusions, particularly
immediately adjacent, usually overlying, a zone of abundant oil and
gas fluid inclusions, is typically indicative of a high chance of
oil in the material. Such analysis can be included as part of the
inventive methods described herein, and, in and of itself,
represents an aspect of the invention. Thus, for example, the
invention provides a method of oil pay zone mapping by solely or in
combination with other methods examining the number of
hydrocarbon-containing fluid inclusions in a material and
identifying areas where the number of petroleum-relevant
hydrocarbon fluid inclusions are relatively low (less than about
10% of the number, e.g., less than about 5% of the number, of fluid
inclusions in water-associated areas, such as a water leg) or not
detectable as areas having a high likelihood of representing oil
pay zones. Of course, this is not true for the pore fluids (present
day fluids present at the site), which can be analyzed by the other
aspects of the invention.
[0154] In another aspect of the invention the method comprises the
step of analyzing released gasses for carbon dioxide. Carbon
dioxide, like water, can be produced from the breakdown of organic
acids contained in the sample. In other aspects, this step is
avoided, as may also or alternatively be the case with respect to
analyzing for the generation of water. This is because either
substance, and particularly carbon dioxide, can be confused with
other sources of the substance, which may make the analysis more
difficult. Nonetheless, in certain instances the analysis of carbon
dioxide in the analyzed gasses, is an aspect of the invention.
[0155] In another respect, methods of the invention can comprise
analyzing the analyzed gasses for the presence of carbon monoxide,
which can be indicative of formic acid being present in the sample
(and, thus, useful in mapping of oil pay zones). Carbon monoxide
can be detected using conventional carbon monoxide detection
devices, which are commercially available, or by using technology
similar to that which is employed in such devices. The carbon
monoxide detection can be used to identify pay zones within a well,
where areas of a well associated with a relatively high amount of
carbon monoxide indicate the presence of petroleum in such an area
(e.g., at a certain depth of a well). Within a well, the presence
of about 35% or more, such as about 50% or more of the maximum
detected amount of carbon monoxide (which can be set as 100%) is
typically indicative of a petroleum-relevant amount of carbonic
acid and/or formic acid, typically formic acid, at such site (in
some cases, the method is focused on the identification of the
presence of carbonic and/or formic acid, typically formic acid,
which will be indicative of the presence of oil in the sample and
related material).
[0156] In another facet, the invention provides methods for
determining the permeability of a formation or composition. Such
methods typically require a multiple aliquot method applied to
samples under different conditions, such as different pressures, so
as to assess the permeability of the sample (and, correspondingly,
the formation).
[0157] Such methods are typically performed with samples primarily
or entirely containing non-fluid inclusion volatile substances. In
other aspects, the methods are performed in materials comprising
fluid inclusions.
[0158] A sample can be, for example, subjected to different
pressures to release different aliquots, and each respective
aliquot analyzed for one more substances, such as hexane (or
methane, propane, pentane, etc.). The relative amounts of the
target material released under both conditions is analyzed with the
output of the analysis being indicative of the permeability of the
sample (and thus the formation). The analysis of such methods can
at first appear counter-intuitive, this is because many samples,
such as cuttings, can either be highly permeable, relatively
impermeable, or contain zones of both high and low permeability.
For example, with respect to hexane, if the application of a first
and relatively weaker vacuum results in a relatively large amount
of hexane being released from the sample and analyzed (compared to
the second aliquot performed under a stronger vacuum), this result
will typically be indicative of low permeability of the sample.
This surprising outcome is because most of the petroleum-related
hydrocarbons that could be lost in the first aliquot in such
material will be lost between the generation of the sample (e.g.,
the drilling that produced the cutting) and the analysis of the
sample for high permeability samples. Therefore, if a greater
amount of hexane or other relevant target substance is released and
analyzed when the first vacuum condition is applied such a result
indicates that the permeability of the sample is relatively low,
because the hexane was not lost between generation of the sample
and analysis. If the sample has relatively greater permeability it
typically will release more hexane on the application of a strong
vacuum, because only the material in the sample with low
permeability will release hexane at such time. Thus, the proportion
of hexane or other target substance released from a first aliquot
and a second aliquot by methods of the invention can be compared to
provide an indication of permeability of the sample is another
aspect of the invention. The other gases analyzed besides hexanes
can also be used in evaluating permeability. In fact, it can be
useful to study the relative permeabilities of the various volatile
constituents of the sample.
[0159] In other aspects, permeability can be assessed by infusing
the sample with a substance, such as noble gas, and then measuring
the release of that infused substance, alone or in combination with
the release of endogenous volatile substances, such as hexane.
[0160] In one aspect, the invention provides a method of
determining permeability of a material by comparing the release of
one or more volatile substances and/or classes of volatile
substances from the same sample from the material under two or more
different conditions that promote the release of volatile
substances from the sample, such as applying two different
pressures to a single sample. In some aspects, this process is
applied to a plurality of samples, such as at least 10, at least
20, at least 50, at least 100, at least 250, at least 500, or even
at least 1,000 samples. In some facets, at least three conditions,
at least four conditions, at least five conditions, or more are
applied to a single sample to aid in the assessment of
permeability.
[0161] In one example of the permeability evaluation method
described above, a first aliquot is extracted from a sample, such
as a cutting from an oil well, at a pressure of about 50 millibars.
A second aliquot can then be extracted from the same sample at a
pressure of about 5 millibars. Permeability can then be estimated
by comparing the data obtained from these two analyses. In other
words, the force required to extract volatiles out of a sample can
aid in the determination of permeability. This is of further
significance in that conventional permeability measurements cannot
be performed on cuttings samples, but, rather, are typically
applied on conventional core or rotary side wall core samples and
are based on the pressure required to push a fluid through a
uniformly shaped piece of rock, usually a cylinder. Typical fluids
used in conventional permeability measurements include helium and
mercury. Such permeability measurements cannot be applied to well
cuttings as they require a coherent volume of intact rock.
[0162] A formula that can be useful in estimating the permeability
using hexanes in accordance with the above-described aspects of the
invention is: 100*(hexanes.sup.aliquot 2-hexanes.sup.aliquot
1)/(hexanes.sup.aliquot 2+hexanes.sup.aliquot 1)). In one aspect,
this formula is used in the determination of permeability. Values
obtained from this expression range from 100 to -100. A value of
100 indicates hexanes were only obtained from aliquot 2 in a
2-aliquot analysis with no hexanes analyzed in aliquot 1, these are
the most permeable samples. A value of -100 indicates hexanes were
only obtained from aliquot 1 with no hexanes analyzed in aliquot 2,
these are the least permeable or the tightest samples.
[0163] The nature of the calculation reflects an unexpected aspect
of the invention. Ordinarily it would be expected that the most
permeable samples will have high hexanes on aliquot 1 and low
hexanes on aliquot 2. This however is not the case. I have
surprisingly discovered that in the most permeable samples the most
easily removed hexanes are lost between the time the rock is
disrupted by the drill bit and its rise to the surface suspended in
the drilling mud, until the sample is sealed in a brass tube either
at the well site, or at some later time. Hence, the most permeable
samples show the least amount of hexanes from aliquot 1 and the
most amount of hexanes from aliquot 2, in the type of method
descried here. Thus, a sample that shows high hexanes on aliquot 1
and low hexanes on aliquot 2 is a sample with very low permeability
such that hexanes are not predominantly lost from the sample by
drill bit disaggregation and transport to the surface in the
drilling mud at residence time under atmospheric conditions before
being sealed in a container, such as a brass sample tube, and
analyzed.
[0164] Permeability in samples analyzed according to these aspects
of the invention can vary as a function of compound size, shape,
mass, and chemical affinities. It is therefore instructive to
consider a range of permeabilities using several of the compounds
that are analyzed, or all of the compounds that are analyzed.
Hexanes can be a preferred measure of permeability for the method
(or inclusion in the method) because under natural conditions prior
to analyses the hexanes should be liquids. And under all analytical
conditions used in our analyses the hexanes should be gaseous. This
then removes any possibility with confusing boiling for
permeability.
[0165] As mentioned elsewhere herein, in some aspects, the method
of the invention comprises analyzing the presence of hydrocarbons.
In some cases, the method comprises the analysis of short
hydrocarbon chain molecules. In other aspects, the method comprises
analyzing both long chain and short chain hydrocarbon molecules.
For example, C2-C15 hydrocarbons, such as C2-C12 hydrocarbons,
e.g., C2-C10 hydrocarbons can be trapped and analyzed using a
cryogenic trap method, and methane can be collected and analyzed
using NCG methods described elsewhere herein.
[0166] The analysis of long chain hydrocarbons is another facet of
the invention which distinguishes it from prior art methods which
are typically performed very quickly and, thus, are incapable of
analyzing such materials effectively, in that such methods do not
sufficiently cause longer chain hydrocarbons to be released from
samples. Where a longer period of time is used to trap materials,
such as where a cryogenic trap/pump is employed for about 10
minutes or longer, such as about 12 minutes or longer, or about 15
minutes or longer, relatively longer chain hydrocarbons can be
capture and then analyzed by the method, which is another
distinguishing characteristic of such methods from the prior art.
Relatively longer chain hydrocarbons means hydrocarbons comprising
a backbone of six or more carbon atoms, such as seven or more
carbon atoms or eight or more carbon atoms.
[0167] In a further aspect, the invention comprises consideration
of pressure changes in the performance of the method. Methods of
the invention can comprise the breakdown of compounds, such as
organic acids (e.g., formic acid, carbonic acid, or acetic acid) to
other compounds (e.g., carbon monoxide and water in the case of,
e.g., carbonic acid, or methane and carbon dioxide in the case of,
e.g., acetic acid), which can result in changes (typically
increases) in pressure in the system because of the generation of
such non-condensable gasses (carbon monoxide and methane).
[0168] In still a further facet of the invention, methods in which
changes in moisture are performed on samples are provided,
particularly after such samples are subject to conditions in which
organic acids, such as formic acid or carbonic acid, can be formed,
particularly from materials present in the sample. For example, in
one aspect the method comprise subjecting samples to conditions
that can form carbonic acid, which may be associated with and/or
may further be broken down under such conditions or other
conditions achieved in the performance of the method to form water,
wherein the presence of such generated water is indicative of the
carbonic acid or formation of the carbonic acid, and thereby
indicative of the presence of oil-related hydrocarbons in the
sample (and the material). For example, subjecting oil well
cuttings to methods described herein wherein gas is released from
the cutting, such as under varying degrees of vacuum pressure,
trapped by a liquid nitrogen trap or a similar device, and released
from such a trap to mass spectrometry analysis, water can be
formed, and such water can be detected by any type of conventional
method, including humidity or moisture detection techniques that
are known in the art. The detection of water can, in some contexts,
provide an indication that oil-related hydrocarbons are present in
the sample and material and thus the method can comprise running an
analysis for changes in moisture, humidity, or otherwise detecting
changes in water content, following application of such methods or
forces on the sample.
[0169] In another aspect, the invention comprises analyzing the
effects of pressure in the formation by examining the sample for
the effects of formation pressures. In such aspects, typically a
number of samples from different areas or depths are obtained and
examined for changes in fluid composition, which can be indicative
of a discrete/large change in hydrostatic pressure between the
different areas of the formation (e.g., from a zone of unusually
high pressure to normal pressure or from a zone of normal pressure
to a zone of unusually low pressure), which can be relevant to how
materials in the formation will behave under different
conditions.
[0170] Any of the analytical methods described herein that can be
applied to analyzed gasses in the methods of the invention can be,
and often are, combined, to provide a more complete analysis. For
example, in one aspect the method includes the step of analyzing
the analyzed gas for the presence of carbon monoxide, increased
water content, and/or presence of C5-C10 hydrocarbons. In another
exemplary aspect, the method comprises analyzing the analyzed gas
for the presence of carbon monoxide and carbon dioxide.
[0171] The methods described above can be practiced with or without
the application of other methods used for the identification,
assessment, and/or characterization of formations and/or materials
therein, such as the petroleum content of a formation. For example,
in one facet of the invention, the inventive methods described
herein are applied without performing conventional fluid inclusion
analysis or gas chromatographic analysis of the material or sample.
However, in another dimension, the methods of the invention can be
performed in combination with such other conventional analytical
methods, so as to potentially enrich the information gathered about
the material. Another method that can be combined with these
methods is to examine samples for fluorescence data which can
provide evidence of oil staining of the sample.
[0172] In one exemplary aspect, the invention comprises combining
information gathered from the primary methods described herein with
information gathered from fluid inclusion analysis. Methods of
performing fluid inclusion analysis are described in my previous
patents referenced and described elsewhere herein. In one aspect
that may be particularly advantageous in certain contexts, the
method comprises performing a fluid inclusion analysis that
comprises analyzing fluid inclusion-trapped oxygen, nitrogen, or
the combination thereof, which are associated with the material.
These non-condensable gasses can provide information about the
paleontological (paleo-exposure) surface of the material, which may
assist with, for example, oil exploration.
[0173] In still another aspect, the methods are practiced in
combination with gamma ray mapping for, e.g., identification of
types of geologic formation, e.g., identification of sands vs.
shales. Including gamma ray mapping as a component of the
analytical method can determine the nature of the formation
material (sand vs. shale). The size of a formation can be relevant
to assessing whether the deposit of the material (e.g., oil) is of
sufficient amount to be economically advantageous for producing the
material (again, typically oil) from the formation.
[0174] In another, more general sense, the invention provides
methods of analyzing the content, such as the organic acid content
and/or water content, of cuttings that were intimately associated
with drilling muds, for example, to perform oil pay zone mapping.
In fact, generation of oil pay zone mapping is a preferred and
particularly advantageous application of this and other methods of
the invention. Most cuttings from oil well sites will be intimately
associated with drilling muds (an exception is an air drilled
cutting). I have discovered that such cuttings can provide a unique
opportunity for analysis of drilling areas. While not intending to
be bound by any particular theory, I believe that the interface
between such cuttings and drilling muds will form physiochemical
structures that retain organic acid contents and possibly other
contents, due to the normal differences in pH of the respective
materials (mud and cuttings). Accordingly, methods of petroleum
analysis, and pay zone mapping, comprising preferentially using
such materials, is an important aspect of my invention. The methods
that can be used to analyze the organic acid content of such
cuttings can be any of the methods that are described herein or
that otherwise are known in the art. What characterizes the methods
of this particular aspect of the invention is that the method, at
least in part, focuses on cuttings that have had such intimate
interactions, thereby likely forming such unique conditions for
maintaining their organic acid content. Again, the application of
methods of this invention to determine the organic acid of such
cuttings is particularly useful in pay zone mapping. This is
because such organic acids are typically in cuttings that are
co-located with petroleum in many geological formations.
[0175] One of the advantageous aspects of the inventive methods
described herein is the application of the invention (such as the
analysis of organic acid content) using samples obtained from fresh
water environments (environments in which the water associated with
most, substantially all, or all of the samples analyzed contains
relatively little or no salt). For example, in certain aspects the
method is performed with water having a saline content of less than
about 10,000 ppm, such as less than about 5,000 ppm, such as less
than about 2500 ppm. In this respect, the organic acid content
analysis methods of the invention can work under conditions where
conventional well logging methods fail, due to the nature of the
fresh (low saline) water present at such sites.
[0176] In still another aspect of the invention, mud-associated
cuttings have retained or captured water/brine from the site at
which the cuttings are generated, and the method comprises
analyzing the water/brine associated with such mud-associated
cuttings, for example by analyzing the conductivity of such
water/brine. Again, most cuttings will be mud associated when taken
from petroleum drilling sites.
[0177] These amounts of water/brine are typically small and the
method may comprise freezing such micro-amounts of water and then
subjecting them to a suitable method for analysis, such as scanning
electron microscopy with energy dispersive x-ray fluorescence,
electron microprobe, and/or an ion probe, or other suitable method,
to analyze the water/brine composition of the water in such
cuttings. Such data can be used by petrophysicists to evaluate the
oil and water saturation of a well as currently determined by
conventional well logging methods. This and other such information
that is obtained from such mud-associated cuttings can be used to
map the presence of oil or other substances from such samples, and,
thus, can be used as another method to perform "pay zone mapping",
in accordance with the invention. In one aspect, the method
comprises only analyzing such brine/water content. These methods
can be particularly important in that resistivity (which today is
successfully based on the presence of brine in a material)
currently is commonly used as a key quantifier of petroleum content
of drilling sites and other geological formations.
[0178] The methods of the invention that involve the analysis of
volatile substances can be performed with any suitable number of
aliquots taken from any suitable number of samples. In some cases,
it can be advantageous to take a single aliquot from each sample in
a set of samples. Thus, the invention provides a method in which a
suitable sample is provided, the sample is subjected or exposed to
forces that cause release of a gas containing an analyzable amount
of one or more volatile substances, and the method includes the
step of capturing (e.g., trapping and concentrating) a first
trappable gas (such as a condensable gas in a system that relies on
condensation of the gas) in or with a media or other means in an
analyzable amount to generate an aliquot, optionally but typically
isolating the sample from the aliquot, and optionally but typically
releasing at least an analyzable amount of the volatile substances
from the trap or collecting means, and thereafter analyzing at
least one aspect of the chemistry of the one or more released
volatile substances. Often it will be the case that the "single
aliquot" will actually comprise a condensable gas component
(sub-aliquot) that is trapped with a first trap and a
non-condensable gas component (sub-aliquot) that typically is
separately collected and/or separately analyzed from the
condensable gas sub-aliquot.
[0179] The forces applied or to which the sample are exposed can be
any suitable forces, such as those described above. In one set of
facets, the method comprises subjecting the sample to a pressure of
at least 1 millibar and less than 1 atmosphere, such as between at
least 1 millibar to about 100 millibars. The sample can be exposed
to such forces for any suitable amount of time. Particularly unique
aspects of the invention comprise applying a gentle vacuum
pressure, such as between about 1 millibar and about 500 millibars,
such as about 1-300 millibars, about 1-250 millibars, about 1-200
millibars or about 2-200, 2-150, 2-100, 3-200, 3-250, 3-100, 5-250,
5-200, 5-100, 1-50, 2-50, 3-50, or 5-50 millibars of pressure for a
period of less than 15 minutes, such as less than 10 minutes, such
as less than about 9 minutes, less than about 8.5 minutes, less
than about 8 minutes, less than about 7 minutes, less than about 5
minutes, or even less than about 3 minutes, less than about 2
minutes, or less than about 1.5 minutes or less than about 1
minute, such as about 0.25-15 minutes, about 0.33-12 minutes, about
0.5-12 minutes, about 0.33-10 minutes, about 0.33-11 minutes, about
0.5-11 minutes, about 0.5-10 minutes, about 0.65-about 11 minutes,
about 0.65-10 minutes, about 0.5-7.5 minutes, about 0.33-7 minutes,
about 0.5-5 minutes, about 0.33-5 minutes, about 0.75-7.5 minutes,
about 0.75-5 minutes, or about 1-10 minutes, such as about 1.5-9.5
minutes, such as about 2-9 minutes, such as about 4-8.5 minutes,
such as about 5-8.5 minutes, or such as about 6-8.5 minutes. The
sample also or alternatively can be exposed to other forces
comprises, such as subjecting the sample to a crushing force,
optionally in addition to one or more other forces such as vacuum
pressure, vibrational energy, or radiation energy, such as laser
excitation, or a combination of any or all thereof. Application of
crushing forces can provide a frackability aspect to the method, in
which measures such as ductility and/or hardness are determined
(e.g., by crushing a flexible container comprising the sample) as
described above. The volatile substances can be analyzed by any
suitable means, typically by means that comprise mass spectrometric
analysis. In some aspects, the method can comprise removing
potentially interfering gasses from the media, but in other aspects
such a step is not practiced or is not necessary. In some cases
these methods are characterized by not heating samples to
temperatures of greater than 100.degree. C. in performance of the
method. In some aspects, the method comprises collecting and
sealing samples at the wells versus loaded in lab samples. Such
methods can comprise collecting and analyzing samples in close
proximity to the well site. For example, the method can comprise
performing the method within 200 feet, such as within 100 ft, 75
ft, or even 50 ft of where the samples are delivered to the
surface. The method may comprise transfer of the samples by
conveyor, pneumatic tube system, or other system to a site, or even
delivery by drone, to a laboratory for analysis, which may be
situated within 0.5 miles, such as within 0.25 miles or even 0.1
miles of the well site.
[0180] In another aspect, these methods are performed in relation
to an active well, such as a well that is under active drilling,
such that the method can provide real-time or near real-time
analysis of samples. For example, in some aspects the difference or
lag time between the site of drilling (location of the drill bit)
and the location of the samples in which the most recent analysis
is performed is than about 50 feet, such as less than about 40
feet, less than about 30 feet, less than about 20 feet, or less
than about 10 feet, 7 feet, 5 feet, or even less than about 1 foot.
Such methods may comprise actually collecting samples in the well
line and, e.g., transmitting the data connected with the hardness
of the samples, such as by crushing or squeezing in-well collected
samples, to the surface through fiber optics, well line vibrational
signaling, or the like. In other cases, the analysis of samples at
the surface of the well can still provide an inexpensive
alternative and/or complement to gamma ray mapping which is
currently performed and a faster analysis than x-ray diffraction
methods currently performed and can still be used as a means of
mapping a material (formation, region), and directing
drilling/fracking operations. Data collected from such operations
can be digitized or otherwise relayed as data through a computer
system and then used to automatically direct or provide information
to human operators through, for example, a graphical user
interface, which can aid in the direction of well site operations.
In some aspects, the method is performed with a well that has
increased mud flow as the compared with current rates of mud flow
so as to provide improved real-time analysis through cuttings,
which may be particularly useful when the real-time cuttings
analysis is performed with cuttings delivered to the surface.
[0181] The data collected in the analysis can be any suitable kind
of data, but, as described herein, will favorably often include
analysis of acetic acid, formic acid, and/or oil saturated water
associated with the sample. The analysis also or alternatively can
include measuring the amount of methane, carbon dioxide, and/or
carbon monoxide that is released from the samples or released from
a volatile compound trap.
[0182] Given the variable nature of materials to be analyzed the
scale of the data that is analyzed in methods that are related to
volatile compounds analysis can vary. This can be true even for a
particularly kind of data as the conditions in which the sample are
collected can vary. For example, with respect to cuttings the age
of the cutting, condition of the cutting and its storage, and the
nature of the materials contained in the cutting can influence the
scale. Thus, in one aspect the method can comprise evaluating the
material either through routine experimentation or by guidance
provided through standards or similar means, such as machine
calibration that is programmed based on the variables (e.g., known
oil wells of a similar nature can be mapped and used as a
calibration for similar wells), to assess the right scale of
measurement for plotting or otherwise analyzing the data, as
exemplified in the Examples provided below. The method typically
then comprises seeking indication of the presence or absence of one
or more of the compounds of interest. Where multiple samples from
multiple locations are taken typically a map or plot will be
generated, again as exemplified in the Examples. In such a case the
method will typically comprise manually or automatically seeking
patterns in the data at the selected scale(s) that will indicate
changes or anomalies or "hits". In some cases, the change in the
amount of a target substance in a scale will be from a "0" or near
0 level, or lack of detection, to the detection of any value above
0. As another example, for example, where oil as a percent of total
rock value is used as a measurement, in some contexts (e.g., rocks
with a porosity of about 8%) a measurement of at least 2% would be
considered "high" oil value, and low values could be set at 0.1% or
lower. By plotting the data clear patterns can be seen. Often
times, a measurement of about 15% of the scale or more (e.g., about
25%, about 30%, about 40%, about 50% or more), would be considered
a "hit". The analytical aspect of a volatiles facet of the
invention also can comprise analysis of two or more types of data,
such as permeability at one depth and non-permeability at another,
e.g., to identify trapped zones of oil that can be very beneficial.
Also or alternatively, various measurements, such as oil saturated
water can be combined with other measurements such as formic acid,
acetic acid and the like, such that one can measure the petroleum
pay zone and formations around the pay zone that are in fluid
communication with the pay as evidenced by formic acid, acetic
acid, and oil saturated water. The combination of permeability and
other information, especially when combined with other data from
conventional means, can provide maps that identify one or more pay
zones in a material/region. Use of data including other
hydrocarbons can further explain the nature of the oil, such as
whether there is heavier or lighter oil present (or otherwise
whether the oil and/or gas deposits are of a similar or different
nature and/or whether gas can be relied on to aid in the transport
of oil to the surface, etc.), and relative petroleum deposit
locations, whether there is a "seal" (low permeability region)
around the oil deposit, and/or oil deposit locations in
relationship to water and other pockets of oil and/or water in the
material/region. Such data can aid in determining whether or not
different pay zones can be obtained together or separately and
under what conditions pay zones can be obtained. Thus, for example,
analysis of such data can reveal whether or not an oil or gas
deposit is compartmentalized with respect to other deposits of oil
in the material/region.
[0183] As stated above, the various disclosures relating to the
methods of the invention can be readily applied to devices and
systems of the invention, which are also exemplified in the
examples provided below. Thus, in another facet, the invention
provides devices that comprise (a) a container or chamber for
receiving and isolating samples of a material and (b) a detection
component capable of detecting the amount of one or more target
volatile substances released from the sample, wherein the substance
comprises carbon monoxide, acetic acid, formic acid, or a
combination thereof, optionally in combination with hydrocarbons,
inorganic gasses, or a combination thereof. In still another facet,
the invention provides a device comprising a crushable component or
material that can contain samples, which when crushed provides
information concerning the strength of the sample (and thus the
material) and a system that comprises such a device and means for
crushing the device (as well as optionally means for measuring the
information, storing the information, relating the information,
etc.). In still another facet, the invention provides devices and
systems that are capable of both analyses.
[0184] With respect to devices that are capable of volatile
substance analysis, a device of the invention typically comprises
an energy input component that promotes the release of volatile
substances from the sample. The energy input component typically is
or comprises (a) a pressure generating device or system, (b) a
device or system that promotes release of volatile substances
through mechanical forces, thermal forces, or both, or a
combination of (a) and (b). Often the device or system will
comprise means (component, system, or the like) for isolating
volatile substances released from the sample from the sample, the
environment, and/or other components of the system or device, such
as one or more operable valves. Devices and systems often will
include a trap, which may be a non-selective or a selective trap,
or comprise both kinds of traps. The trap can be, for example, a
liquid nitrogen trap, which is capable of capturing volatile,
condensable gasses, released from samples, such as cuttings. The
dimensions of such devices are described elsewhere herein, as are
suitable materials from which such devices can be made.
[0185] Devices for volatile compound analysis typically include
means for measuring the volatile substances. This can include,
e.g., a carbon monoxide detector or other kind of chemical detector
and also or alternatively a less specific detection system, such as
a mass spectrometer, examples of which are provided elsewhere
herein. Where advantageous, the analytical parts of the system may
be optionally isolatable from other parts of the system, such as to
ensure proper operation and/or to avoid false signal events. The
device/system of the invention may further comprise a programmable
or data logic component for collecting data, relaying data, storing
data, and the like, which may include alarms, automatic device
means (such as means for controlling directionality of a drill),
and/or a graphical user interface. The operation of the components
of the device/system can similarly be automated and/or placed under
control of a programmable unit or computer system.
[0186] In another aspect, the invention provides systems or devices
for chemical analyses of volatile compounds in a sample of a
material that comprises (a) a cryogenic trap that can be cooled and
held at temperatures that are capable of capturing target volatile
substances when such substances are in fluid communication with the
trap (e.g., temperatures of about -100 degrees C. or colder, such
about -110, about -120, about -130 degrees C. or less) (e.g., the
device/system will typically include a cooling component or cooling
means that is capable of selectively cooling the cryogenic trap,
which can be in practice one, two, or more separate traps); (b)
optionally, but typically, a component or system for selectively
warming the cryogenic trap in a controllable manner, (c) one or
more devices or systems for applying one or more forces to samples
that the system is applied to, such as a vacuum system, preferably
with the ability to apply multiple levels of vacuum pressure to the
sample, and in preferred aspects the ability to apply relatively
low/gentle vacuum on a sample, such as about 25-150 millibars of
pressure (e.g., about 60-120 millibars of pressure) to a sample,
(d) components for containing the volatile substances and keeping
the substances isolated from the environment, such as a housing,
(e) components for selectively isolating the trap from the sample,
such that volatile compounds can be exposed to the trap only after
cooling to a desired temperature, (f) an optional component for the
capture of volatile substances that will not condense on the trap,
which typically is selectively isolated from the other substances
such that the noncondensable materials can be separately analyzed
from the materials that condense on or otherwise bind to the trap
and are thereafter released from the trap, and (g) a device for
analyzing at least some of the volatile substances released from
the trap, such as a mass spectrometry device, optionally with
means/components for selectively allowing access of the volatile
substances to the analytical device (e.g., one or more selectively
openable valves), and (h) means or components for causing the
transport of at least some of the volatile substances captured in
the enclosed system. Such a system may also or alternatively
further comprise (i) a component or means for evacuating any
noncondensable gases out of the cryogenic trap as and if necessary
without release of any condensable volatiles from the cryogenic
trap if the analytical method requires high vacuum, such as a
selectively operable pumping system. Systems that have
means/components for analysis of non-condensable gasses/materials
may further comprise means for capturing a set volume of such
non-condensable materials, such as selectively operable vacuums
that can act on such materials and/or components/means for
selectively exposing such materials to the analytical part of the
system and often means/components for transporting such materials
to the analytical componentry of the system/device.
[0187] As described above, a cryogenic trap can be generated by
contacting a suitable medium with a cryogenic substance such as
liquid nitrogen, liquid argon, liquid oxygen, liquid air, liquid
helium, dry ice, a dry ice slurry, normal ice, a normal ice slurry
of water ice in fresh water, a normal ice slurry of water ice in a
saline brine, or any other naturally cooling substance capable of
achieving the minimum temperature required to freeze the
substance(s) of interest onto the cryogenic trap. A cryogenic state
may also or alternatively be achieved with mechanical refrigeration
or cooling as may be achieved with a Kelvinator device. The
Kelvinator or other cryogenic device must be able to achieve the
minimum temperature required to freeze the substance(s) of interest
onto the cryogenic trap.
[0188] A cryogenic trap component can have any suitable
configuration. In one exemplary embodiment, the trap will be
configured such that cooling of the cryogenic trapping device
occurs on the exterior of a cryogenic chamber and volatile
substances adhere to the interior of the cryogenic chamber.
Alternatively, a trap can be provided wherein cooling of the
cryogenic device occurs on the interior of the cryogenic chamber
and volatile substances adhere to the exterior of the cryogenic
chamber.
[0189] In one aspect, the cryogenic trap comprises one or more
materials that are suitable for cyrogenic trapping, which typically
are selected from materials that comprise one or more suitable
metals, such as aluminum, copper, gold, silver, platinum,
palladium, stainless steel, brass, bronze, nickel, cobalt, or any
other appropriate metal, including alloys and/or any suitable
combinations of such materials. A trap also or alternatively can be
composed of a non-metallic material, optionally a non-metallic
material that forms a substrate for trapping of volatile
substances, such as, for example, carbon fibers, peek, natural or
industrial diamonds or diamond films, glass, ceramics, or any other
appropriate non-metallic substance or combination of such
substances, alone or in further combination with one or more
metallic substances. The trap can have any appropriate shape or
configuration, including, for example, a shape selected from
cylindrical, a u-tube, polygonal, sphereical, funnel shaped,
ribbed, helical, and/or botryoidal shape, or any other appropriate
shape.
[0190] A system or device comprising a cryogenic component or
system according to such aspects of the invention can be configured
to analyze any type of volatile compounds or volatile
compound-associated sample(s). While the description herein places
significant focus on extracting volatile substances from geologic
materials, especially from materials from oil and gas wells, and
particularly from cuttings from oil and gas wells, the methods of
the invention can be performed, as stated already herein, with
other types of samples and in another facet of the invention may
even be practiced with volatile fluids that are independent of any
kind of solid sample. For example, in one aspect one or more
volatile analysis methods of the invention, such as those described
above, is also or alternatively applied to a liquid, such as one or
more drilling muds. In another aspect, such a method or set of
methods is also or alternatively applied to a gaseous substance
(e.g., a substance that is substantially, predominately, or
entirely in a gaseous state under normal atmospheric conditions).
In such aspects of the invention the inventive method can comprise
filling a container or a component of the system with the gas to be
analyzed and allowing the gas to make contact with a trap, such as
a liquid nitrogen trap, and then subjecting trap-released gasses to
analysis, such as by mass spectrometry. Where the gas is provided
in a container, such as a vial, the method can include the step of
filling the vial, optionally sealing the vial, and optionally
forming a fluid flow in a sealed manner between the vial and the
system such that volatile substances in the gas are not lost either
due to escape or reaction. Alternatively, gas can be captured in a
device, such as a syringe, and introduced into a system, e.g., a
system under vacuum, by passage of a needle through a septum, and
thereby emptying some, most, all, or essentially all of the
components of the syringe into an inlet into the system and
eventually, immediately, or near immediately thereafter into an
inlet to a trap and thereafter an analytical device (or where a
trap is not used, directly to an analytical device according to
such aspects of the invention). Yet another alternative facet of
the invention provides a method in which a gas containing amounts
of volatiles, such as very low/trace amounts of volatiles in the
gas, is to permit condensation of the gaseous volatiles on a trap,
such as a liquid nitrogen trap, over a relatively longer period of
time, to allow accumulation of even trace amounts of volatiles on
the trap. Such a process could be used to detect extremely small
amounts of explosive associated volatiles in air, or of trace
amounts of hydrocarbons and/or organic acids in air associated with
petroleum seeps or other relevant trace chemicals such as
environmental contaminants. As such, such an instrument, and even
many of the other devices and systems described herein, may be
useful deployed as a mobile unit in a car, truck, plane, boat, or
even a rocket. A system with multiple liquid nitrogen traps would
provide continuous monitoring as while one trap was extracting a
sample to analyze, another trap would be analyzing the previously
trapped sample.
[0191] Systems and devices of the invention will typically comprise
a device or a means for introducing volatiles from a sample into
the system in an isolated manner. In one advantageous aspect, as
exemplified elsewhere herein, the system includes componentry
and/or means for introducing volatile substances to the
device/system by way of syringe or needle injection, which often
advantageously comprises a portion that punctures, pierces, or
otherwise traverses a septum, which typically will be associated
with a sample container in which the samples can be contained,
preferably in a sealed state, such that loss of volatile substances
is minimized (e.g., the system can comprise one or more samples
that are hermetically sealed to a cryogenic trap inlet). The system
will typically comprise componentry/means for generating flow of
gasses to the cryogenic trap, such as pumps and the like. The
system may further optionally comprise sources of gas, such as air
or other gasses, which can aid the flow of volatile substances in
the system/deice.
[0192] An analytical device for the assessment of volatile
compounds according to such aspects of the invention typically
comprises a mass spectrometer, but also or alternatively can
comprise one or more additional analytical devices including, for
example, a gas chromatograph; an infrared spectrometer; a Raman
spectrometer; or any combination of these including multiples of
the same type device (e.g., multiple mass spectrometers); or any
other appropriate analytical means and/or combination of analytical
means. As described elsewhere the device/system will often include
programmable logic means/components that can put the operation of
the device under automatic control and capture, record, and/or
transmit and/or display data obtained from the performance of the
method in digital form, print form, or in other known forms.
[0193] The combination of the above-described components into
devices and systems provides several useful and novel additional or
alternative aspects of the invention. Thus, for example, the
invention provides a novel and useful device that comprises (a) a
cryogenic trap device/component that is in fluid communication,
typically selective fluid communication, with one or more mass
spectrometers, usually in a configuration such that permits the
release of material from the cryogenic device/component to the mass
spectrometer component. Such a device can comprise means/components
for flow of material through the system and means/components for
selectively heating the cryogenic trap.
[0194] In another aspect the invention provides devices and systems
comprising (a) a non-selective trap that can capture volatile
substances in sample of materials, (b) a housing or other enclosure
that prevents loss of volatile substances in materials in the
system (at least to significant amounts, such as by maintaining at
least 90%, at least 95%, at least 98%, or even 99% o more of the
volatile substances associated with the sample once the sample is
placed in a secure manner in communication with the system), (c) an
analytical device that can detect one or more primary and/or
secondary compounds that are associated with target materials, such
as oil and/or natural gas, (d) components or means for transporting
volatile substances to the trap and (e) components or means for
selectively releasing materials from the trap in a manner that
allows for determination of the presence or absence of at least
one, preferably at least two, and typically 3, 4, 5, or more (e.g.,
at least 6, at least 7, at least 8, or even 10 or more) substances
from the system. Typically such a system will further comprise one
or more forces that can be applied to the system for promotion of
the release of volatile substances, such as different pressures,
which may reveal additional information elements concerning the
substances such as permeability of the sample and/or will comprise
means/components for causing chemical reactions of the volatile
substances, for example by producing water in the system from one
or more trapped substances. The systems can also include
means/components for selectively crushing/squeezing the samples and
providing a related measurement thereto such that compressibility
and the related ductility/hardness of the sample can also or
alternative be provided. The sample containers provided by the
invention are also novel and useful devices in and of themselves.
Thus, for example, the invention provides a sample container
comprising a selectively puncturable section, a housing that is
capable of containing sample materials, such as oil-well associated
cuttings, and that also is at least substantially impervious to the
release of volatile substances, and optionally a crushable
selection or component that allows for the application of
crushing/squeezing forces on the container, in a known manner,
resulting in a measurable amount of compression of the container
that provides relative information about the hardness/ductility of
materials in the container and also optionally promotes the release
of volatile substances. Optionally and often such a container is
configured to be in sealed fluid communication with one of the
devices of the invention.
EXEMPLARY EMBODIMENTS & APPLICATIONS OF THE INVENTION
[0195] The following examples further illustrate various aspects of
the invention but should not be construed as in any way as limiting
the scope of the claims or the rest of the disclosure provided
herein.
Example 1
[0196] This example provides a description of an exemplary
device/system according to certain aspects of the invention and
that also is suitable for application of several of the inventive
methods described herein. An overview of the exemplary device is
provided in the following figure (FIG. 1).
[0197] With respect to the device/system shown above, #1 depicts a
first sample container, as described elsewhere herein. The first
sample container #1 contains the sample of the material, such as
cuttings taken from an oil well. The sample container #1 in the
case of the depicted system is sealed and made of an impermeable
material. The top portion of any sample container used in the
system, such as the first sample container #1, is penetrable by the
needle #2, which provides a passageway and means for transferring
gasses released from the sample into the rest of the system, either
immediately after penetration and/or after generation through the
application of one or more forces acting upon the sample.
[0198] A second sample container #2 and a third sample container #3
are also shown, reflecting the fact that systems of the invention
often are run with numerous samples in a given run or load (e.g.,
at least 5, at least 10, at least 15, at least 20, at least 25, at
least 30, at least 35, at least 50, or more samples). In the case
of the depicted system, a sample carousel, #4 is provided, into
which the several samples to be analyzed in the particular run are
loaded. Other types of automation other than a carousel could also
be used, such as a cartridge holding a plurality of samples in
either a vertical or horizontal profile (not shown), or in any
angle between vertical and horizontal, that can deliver samples in
any position appropriate for volatiles analyses (also not shown).
The samples loaded in a particular load or run typically are
related to one another, such as samples taken from a particular
well site and maintained under particular conditions, but this is
not necessarily always the case. In some embodiments of the
invention, the carousel #4 is automated to run once the analysis on
a particular sample is complete, often this will be controlled by a
programmable computer which is connected to the system and in
control over various functions operating in the system (and thus
components of the system). Thus, for example, when analysis has
been completely performed on the first sample container #1, the
carousel can automatically rotate placing the second sample
container #3 into position, whereby a penetrable portion of that
sample container, can be penetrated, such as by the needle #8. The
loading and transferring need not be in the form of a circular
carousel, but could be, for example, in the form of a conveyor, or
any other suitable sorting mechanism. The penetration of sample
containers by the needle can, also, be under automatic operation
or, more typically, is subject to operation by robot or computer
once certain conditions have been satisfied (and subject to manual
override). The sample containers depicted here comprise sidewalls
that are made of a sturdy but crushable/collapsible material, such
as brass, of a relatively fixed thickness.
[0199] The depicted system also comprises a ram #5 which is made of
a material that is suitably composed and configured such that it
can deliver an impact on the crushable sidewall or other modifiable
portion of the container. For example, ram #5 may be made of a
stronger metal, such as steel, which can repeatedly be used to
crush the sidewall of the container and thereby deliver a crushing
force to any sample materials contained therein, such as oil well
cuttings. Ram #5 is typically connected to pistons #6, which can be
air pistons or another suitable type of piston(s). Pistons #6 and
ram #5 typically form a squeezing or crushing apparatus or system
together, as depicted. The pistons #6 can be used to drive the ram
#5 into the crushable portion of the sample container, e.g., #1,
either upon a user command, under some automatic condition, and/or
when directed by a computerized control system. The ram is
typically driven by the piston or other driver mechanism (e.g., a
powerful spring) into the container with a force that is suitable
for crushing a portion of the container and delivering enough force
to crush the sample material, thereby either releasing volatile
compounds or assisting in the release of such volatile compounds in
combination with the application of other forces or energies, such
as vacuum pressure. The system typically comprises an anvil, #7,
which assists in the crushing of the container, #1, by providing a
hard surface against which the container is pressed when the ram #5
is brought into contact with the container #1 by application of the
pistons #6.
[0200] The needle #8 also is typically associated with a needle
assembly, which comprises a connection block #9, which, as
depicted, is connected to a leveling screw, #10, which can raise or
lower the needle, so as to cause the needle #8 to puncture a seal
or other puncturable portion of the container #1 when engaged
(alternative devices or means for raising and/or lowering the
needle also or alternatively could be used). Engagement can be
performed manually, automatically, and/or by computerized program
control. The connector block #9 comprises a channel portion that
gas passing from the sample container #1 and through the needle #8
can flow. In the depicted embodiment, the channel portion of the
connector block #9 is in communication with a selectably engagable
(closable/openable) right-angle valve #11, which controls the flow
of gasses from the sample container/needle/connector block into the
other portions of the system. "In communication" in the context of
the depicted device means that gas can flow between the chambers,
elements, or devices being described as being "in communication."
The first right-angle valve, #11, as with other components, can be
opened or closed manually, automatically, and/or under control of a
computer, attached to the system, so as to practice the methods of
the invention. In some cases, for example, the valve is closed to
allow for controlled release of gasses from the sample container #1
into the rest of the system. The control afforded by inclusion of
this first right-angle valve, and other valve controls in the
depicted system, can, for example, permit different "runs" of the
system on a single sample, under different conditions, such as
under the application of different vacuum pressures on the sample.
Other types of valves, such as ball valves, in-line valves, or any
other type of valve that can satisfactorily operate in a vacuum
system (not shown) could be used instead of right-angle valves as
are exemplified here and described in any part of this
disclosure.
[0201] Another two right-angle valves (#12 and #13) are connected
to and in communication with the first right-angle valve, #11, and
respectively control the flow of dry nitrogen into the system and
the flow of gas from the sample in container #1 into the liquid
nitrogen trap container. Other purge gases such as dry air, argon,
oxygen, helium, and others also or alternatively can be used as the
purge gas instead of dry nitrogen. Similarly, other cryogenic
fluids such as liquid oxygen, liquid argon, liquid helium, and any
other suitably cooling fluids also or alternatively could be used
as the chilling means instead of liquid nitrogen exemplified here
and described elsewhere herein.
[0202] The right-angle valve exterior is connected to a flexible
vacuum hose, #14, which accommodates the up and down motion of the
needle assembly raising and lowering into various sample containers
(#1, #2, #3) on the carousel (#4). The vacuum hose #14 also is used
to allow flow of gases to create vacuum pressure and to also allow
sample gasses to pass further into the system. A pressure gauge #15
provides the operator with pressure conditions in the system, and
thereby provides a check on whether the system is operating as
expected, which is important to ensuring the validity of
experiments and analyses performed in the system (other
means/devices for measuring pressure also or alternatively could be
used). A fourth right-angle valve #16 controls access to a
diffusion pump #16a, (which typically are directly connected, as
shown), which is used to expel gasses from the system (alternative
means and devices for pumping also or alternatively could be
included in such a system). A fifth right-angle valve, #17,
provides a second inlet control on the liquid nitrogen trap
container. As already mentioned all of these valves are
controllable and control over the valves can be configured to
operate in any suitable manner, so as to perform the various
methods of the invention.
[0203] A relatively long first tube, #18, which is typically
comprised of aluminum or a similar material, provides communication
between the right-angle valve #17 and the liquid nitrogen cooling
chamber, #20, which also acts as the exterior of the liquid
nitrogen trap components of the system. Along the tube #18, one or
more heater(s), #19a and #19b, can be placed, which allow for the
application of heat, in a relatively predictable manner, to the
system, which will aid with the release of gasses frozen to the
liquid nitrogen trap. The heaters can be any suitable type of
heaters, including units that radiate heat, that blow hot air, or
that heat the tube by other suitable means. Typically, heaters
(#19a and #19b) are placed at the ends of the first tube #18.
[0204] The liquid nitrogen cooling chamber #20 is the exterior of
the liquid nitrogen trap freezing region. Here gas can come into
contact with the liquid nitrogen cooled componentry of the system
and freeze onto the trap. The flow of liquid nitrogen is controlled
by a liquid nitrogen valve, #21. A thermocouple, #22, provides the
user with the ability to monitor the temperature of the system, and
optionally can be configured to send information to an associated
computer system, which may control certain functions of the system.
The liquid nitrogen trap has its own temperature controller, #23,
which helps in controlling the application of liquid nitrogen. A
sixth right-angle valve, #24, is positioned at the exit of the
liquid nitrogen trap region and controls the flow of gasses from
the trap into the remainder of the system. A specialized
right-angle valve, the release valve, #26, is a pin hole bypass for
analyzing gas that is released upon warming of the liquid nitrogen
trap due to operation of heaters, #19a and #19b. As described
generally above, liquid nitrogen is applied to this region of the
system, lowering the temperature to a point at which volatile
compounds contained in the sample can freeze to this trap region.
The application of the heaters then permits the release of the
frozen gasses from the region to the remainder of the system,
including the mass spectrometer, #31.
[0205] A pin hole apparatus, #25, is configured to regulate flow of
non-condensable (noncondensable) gasses from the noncondensable gas
trap, #27, into the mass spectrometer, #31. The noncondensable gas
trap, #27, is configured to collect gasses that will not bind to
the liquid nitrogen trap. The noncondensable gas trap #27 comprises
a right-angle valve, which allows for selective opening of this
part of the apparatus, such that the gasses released from the
warming of the liquid nitrogen trap are kept separate from the
noncondensable gasses.
[0206] Diffusion pumps, #29 and #33, which may be backed by
roughing pumps, provide flow and pressure control in the system,
and are controlled by respective valves, #28 and #32. Often, any
other type or types of suitable high vacuum pump(s), such as
turbomolecular or cryogenic pumps or any other types of high vacuum
pumps can be used instead of where diffusion pumps are cited in any
part of this application. Control via manual operation or the
computer system provides different amounts of pressure (positive or
negative) in all or parts of the system, through the operation of
these pumps. As discussed above, in operation several runs of the
system can be performed on even a single sample by "pulling" on the
sample through the application of different vacuum pressure
conditions, thereby releasing different amounts of different
gasses, thereby forming different aliquots from a single
sample.
[0207] Access to the mass spectrometer, #31, is controlled by a
mass spectrometer valve, #30. Any suitable mass spectrometer can be
used in the system, and many are discussed above. The mass
spectrometer #31 is configured to send information to a
computerized system (not shown), typically via a data output
connector (shown as wires connected to mass spectrometer #31),
indicating the presence of target compounds of interest, such as
hydrocarbons, inorganic gasses, carbonic acid, acetic acid, or
another organic acid, or the anticipated breakdown products
thereof, such as water or carbon monoxide.
Example 2
[0208] This example demonstrates the use of methods of the
invention to determine oil and water saturation in a formation
based on analysis of cuttings taken from an oil well, as well as
permeability analysis obtained by analyzing a series of cuttings
taken from the well.
[0209] Thirty samples of non-sealed cuttings taken from different
depths in an oil well that had been stored in unsealed containers
for a period of approximately three months under warehouse
conditions in the summer (about 100-130 degrees F. estimated
maximum daily temperature) were subjected to analysis using a
device as described in Example 1 to provide information concerning
the permeability of samples taken from different depths in the oil
well, based on the release of target substances. The cuttings were
subject to two runs of the system, forming two aliquots, based on
the application of pressure conditions of 50 millibars and 5
millibars, respectively.
[0210] The right-hand column of FIG. 2, shown below, depicts an
actual plot of the relative permeability of these samples, provided
by two conventional permeability methods (e.g., the downward
pointing triangles #1 are conventional sidewall oil core
permeability measurements; curve #2 represents permeability
assessments made through conventional well logging methods) and by
application of the inventive method (upward pointing triangles,
#3), as applied to cuttings from an oil well site. This data
represents one of the first times that permeability information
from a site was obtained from oil well cuttings, and the data shows
that oil well cuttings can provide permeability information which
correlates well with data obtained from significantly more
expensive traditional methods. The permeability data was plotted
either in millidarcies or in relative proportion to other
permeability measurements using conventional techniques.
[0211] Other information included in FIG. 2 is a plot of mud
logging data (gas chromatography data), in the second column from
the left, indicating the presence of C1-C5 hydrocarbons in muds
obtained from the respective plotted depths of the well (y
axis).
[0212] The middle column provides Sw plots obtained from various
methods (the continuous line, #4, represents data from conventional
well logging and the dots, #5, represent data taken from sidewall
coring methods). The triangles, #6, are data obtained by the
inventive method being applied directly to cuttings from the well.
The results demonstrate a strong correlation in terms of Sw, here
being obtained directly from cuttings and also and from more
conventional and often more expensive conventional methods. This is
another breakthrough aspect of the invention, obtaining both
permeability and Sw data from cuttings in a single run and
providing a comparative analysis of such data, for different depths
of a well, against other conventional methods of assessing a well
site.
[0213] Other information provided in FIG. 2 include the mud log
resistivity curve, data from oil staining on cuttings, caliper data
(measuring bore hole sizes, red dashed lines), and conventional
gamma ray data (which provides information about the type of
material at the site--such as shale versus sandstone, carbonate,
etc.) (plots in the first column on the left). Correlation of this
information was used to identify the zones, which are indicative of
the presence of oil, as marked by the vertical bar on the very
left, #7. The water leg below the oil pay zone is indicated by the
lower vertical bar on the left, #8.
[0214] In this data, conventional resistivity data failed to
convincingly identify the presence of oil that could be detected by
the method of the invention. This may be due to the inability of
resistivity data to differentiate between oil and gas, because both
compounds are non-conductive. This is one potential advantage of
methods of the invention exemplified by this example. The zone of
the most abundant oil fluid inclusions was the water leg #8, not
the oil pay zone #7. Thus, use of the previously described fluid
inclusion methods on this well also failed to identify oil pay
zones, which could be identified by the cutting methods of the
invention, thereby also reflecting a benefit of the inventive
method.
Example 3
[0215] This example demonstrates the identification of an oil pay
zone, through application of the inventive method on oil well
cuttings, which were taken from a section of an oil well that was
not being prospected based on application of pre-existing
analytical methods.
[0216] Five hundred and eighteen cuttings taken from an oil well
site, sealed at the well, were used in this analysis. Three
aliquots were obtained from each cutting, using pressure conditions
similar to those described in Example 2, plus an aliquot following
intense sample dehydration. Permeability measures were obtained by
the difference between aliquots 2 and aliquot 1 for each cuttings
sample, #1. The data from the analysis were plotted and the actual
plot of this data is shown in FIG. 3.
[0217] Numerous additional data points were also obtained and are
reflected in FIG. 3, such as formic acid #2, acetic acid #3, oil
saturated water #4, presence of C5-C10 paraffins #5, C6-C10
naphthenes #6, C6-C8 aromatics #7, and total oil #8. The gas
components methane #9, ethane plus propane plus butanes #10, and
Total Gas #11 are also plotted, as is the sum of the oil and the
gas #12. Oil and gas-indicating measurements were obtained by the
sum of the results of all three aliquots. The quality of the oil
and gas product is indicated by the C8/(C5+C6+C7+C8) curve which
helps differentiate heavier oil that plots to the right versus
lighter oil and gas that plots to the left. The GOR (gas to oil
ratio) curve #14 helps determine gas prone versus oil prone zones.
The paraffins/(paraffins+naphthenes) curve #15, and the
aromatics/(aromatics+naphthenes) curve #16 are used to evaluate the
quality of the oil and discriminate various different oils from
each other.
[0218] This data reflects the identification of a discrete oil pay
zone. The low permeability region #17 on the graph reflects a tight
zone overlying an accumulation. Below this tight zone (a zone of
low permeability, generally less than about 10 millidarcies, and
typically below about 1 millidarcy) (a tight zone that overlies pay
keeping it from migration in the material can be considered a
"seal") (these terms are also subject to general understanding in
the art), two oil containing zones were identified through the
assessment of the various basic data points. The upper zone #18 had
been missed by previously applied, conventional methods, but was
identified through analysis of oil well cuttings, using the methods
of the invention, whereas an actual oil producing zone #19 was
confirmed by the application of the various methods of the
invention on oil well cuttings.
[0219] A simplistic interpretation of this data is reflected in
FIG. 3b, which specifically reflects and focuses on key signals in
the permeability and oil saturated water data that characterize the
geologic formation (material) studied in this Example.
Specifically, the permeability data reveals a tight zone, #17, with
little permeability, above a non-target zone identified by oil
saturate water according to the inventive method employed in this
Example, #18, as well as the confirmation of a zone identified
through other conventional methods, #19, through oil saturated
water analysis.
[0220] The concept of "oil saturated water" has been developed as
part of the invention described herein. "Oil saturated water"
refers to water that has chemical indications of fluid
communication with oil. Specifically, samples indicative of
containing oil saturated water refers to those samples that show
relatively high amounts of the indicator compounds formic acid,
acetic acid, carbonic acid and/or bicarbonate, often from the
presence of their breakdown indicator compounds, especially carbon
monoxide and/or water, or from a combination of detection of such
primary and secondary indicators. Any of these conditions can be
combined, such as, for example, methods of the invention can
include determining the amount of water, one or more other
inorganic gasses (e.g., one or more of hydrogen, helium, nitrogen,
argon, oxygen, hydrogen sulfide, carbonyl sulfide, carbon
disulfide, and/or sulfur dioxide), carbon monoxide, carbon dioxide,
carbonic acid, acetic acid, formic acid, methane or other C1-C5
hydrocarbons, and/or bicarbonate that is associated with/released
from a sample as a means for determining if the same is associated
with target substances, such as oil and/or natural gas. Conditions
of analysis typically must be at least partially controlled in
order for water to provide an indication of such material and,
thus, communication with oil in a geologic formation. Thus, with
respect to a device/system, such as that exemplified in FIG. 1, and
described above, water is advantageously released from the liquid
nitrogen trap at a temperature colder than the usually water
sublimation temperatures in the device/system, usually about 55
degrees centigrade. Some of this water can then be detected at very
low liquid nitrogen trap temperatures, such as about -140 degrees
centigrade. Water with high amounts of the indicator compounds can
be considered oil saturated water, whereas water without these
indicator compounds is not oil saturated water. This
characterization of water in a formation cannot be made with
conventional methods, especially in zones with very high water
saturation, where conventional well logs essentially provide no
information as to whether or not that specific water is in
communication with commercially viable oil and/or gas
accumulations. The determination of the presence of the indicator
compounds by the inventive analytical methods provided here allows
this important distinction to be made. This tool can then be
applied to wells that don't encounter commercially viable
quantities of oil and/or gas, i.e., dry holes, to determine if such
large commercially viable oil and gas occur close to the location
of the dry hole, or not. These analyses could also be performed at
the well site, and indicated zones of nearby oil and gas could be
targeted with side track wells drilled from the initial pilot well
at the fraction of the cost of drilling another well to explore for
the nearby pay zone at a later date.
[0221] This Example shows that cuttings-derived data, such as
permeability and oil saturated water, can be used to determine the
presence of oil and to also determine permeability and discrete
geologic zones containing oil, even ones missed by other,
conventional methods.
Example 4
[0222] An analysis was performed as described in Examples 2 and 3
on 139 cuttings that were sealed at the well or the deeper section
of the vertical pilot oil well described in Example 3, other
samples were taken from a lateral line drilled as a sidetrack from
the pilot well following the evaluation of the pilot hole to locate
the deep pay zone. Three aliquots were analyzed for each sample
under the pressure conditions described above in Example 3. The oil
saturated water results are shown in FIG. 4a (labeled element
#1).
[0223] The oil saturated water anomaly in the vertical pilot well
reveals an oil rich pay zone #2, which then became the target for
drilling and fracking the lateral sidetrack. High water saturations
are indicated above #3 and below #4 the oil pay zone #2. To be able
to use this information to aid in deciding at what depth to drill
and land a lateral sidetrack to a pilot hole requires very quick
analytical and interpretive turnaround time. Usually the
interpretation needs to be delivered within 24 hours of the
vertical pilot well reaching its total depth. Samples are often air
expressed back to the lab, or hot shot by car if close enough, once
or twice a day so the analyses can keep up with the drilling of the
well as much as possible.
[0224] The oil saturated water data of the lateral sidetrack #5
shows the lateral was in the oil pay zone #2 penetrated by the
vertical pilot well for about 2,700 feet, this is shown as #6.
Following drilling in the oil pay zone #6 for about 2,700 feet the
lateral sidetrack drilled through a zone of low water saturation
for about 1,000 feet #7. At the end of the lateral sidetrack, the
oil pay zone was re-entered for about 500 feet #8. The lateral's
well track #9 shows that the deepest part of the lateral was at the
beginning of the lateral. The lateral continued to drill shallower
and stay in the oil pay zone #6 until the bore hole became
sufficiently shallow that the lateral was no longer drilling in the
oil pay zone #6, but that further drilling was above the oil pay
zone and in the shallower water leg #7. Towards the end of drilling
the lateral the well's track dips back down as shown towards the
end of #9. Dipping back down results in the borehole re-entering
the Oil Pay Zone as #8, as revealed by the oil saturated water
curve #5.
[0225] A stylized/simplified representation of certain elements of
this data is provided in FIG. 4b. Specifically, vertical zones of
water #3, oil #2, and water #4 zones are plotted, with oil
saturated water #15 along the well track #9 identifying lateral
zones of oil #6, water #7, and oil, #8. This reflects the ability
of methods of the present invention to be applied to wells that
have both vertical and lateral characteristics, and to provide
"maps" of data in both directions, even in a single well or
area.
[0226] This Example demonstrates that the methods of the invention
can allow for real-time data collection at the site of a lateral
being drilled, such that this real-time data can be used to help
"steer" (direct, guide) the direction of the lateral, so as to keep
the borehole in or very close to the oil pay zone.
Example 5
[0227] This Example demonstrates application of a method of this
invention to distinguish between oil pay zones and gas zones in a
well site.
[0228] In this Example, 205 sealed oil well cutting samples were
subjected to analysis as described above. Three aliquots were
obtained from each sample, under the discrete pressures (25
millibars, 1 millibars, and 0.1 millibars)
[0229] SW was calculated from conventional petrophysical data,
indicating the presence of hydrocarbons in the geologic formation
at the site. However, SW cannot distinguish between water and gas
deposits, as discussed above.
[0230] The results of the various data obtained by the performance
of the method, such as acetic acid and formic acid information, are
plotted in FIG. 5. A stylized interpretation of this data is shown
in FIG. 5B using the same numbering scheme as in FIG. 5.
[0231] A post-drilling appraisal of the target indicated the well
under analysis in this Example was a gas well and as such was not
economic and was abandoned. Conventional well logs indicated a
large pay zone #1 of several hundred feet in thickness overlain #2
and underlain #3 by strata having high water saturations. The well
was perforated and tested at about the middle depth of the pay
zone. The well flowed gas. At that time the operator abandoned the
well thinking the pay zone was all gas.
[0232] Analyses using methods of the invention, however, indicates
the bottom 200 feet of the pay zone to be oil #7. This
determination was based on high total oil responses #4, high acetic
and formic acid responses #5, and high oil saturated water #6. The
remaining pay zone above the oil pay is then gas #8, as tested.
Above the gas are strata with high water saturations #9, and below
the oil pay are strata with high oil saturations #10.
[0233] The data shown in FIGS. 5 and 5B demonstrates that
cutting-derived data obtained by applying methods of the invention
can distinguish between oil and gas pay zones, which is of
significant economic importance.
[0234] The data shown above demonstrates that cutting-derived data
obtained by applying methods of the invention can distinguish
between oil and gas deposits and also can confirm conventional core
analysis information. As conventional core analysis is
significantly more expensive and more time intensive than the
cutting analysis of the invention this provides yet another
important benefit of the inventive methods.
Example 6
[0235] The methods of the invention can be applied to large
regional areas or wells that span large regional areas to provide
plots of entire fields, regions, or cross-regional wells. The
identification of acetic acid and/or formic acid and/or oil
saturated water in cuttings can indicate that although that a
subject well is a "dry hole" (a well not producing appreciable
amounts of oil or gas), the well is nonetheless in proximity to a
field. This data can then be used as a means for guiding
exploration from the well site in terms of lateral drilling or the
drilling of new, nearby wells. A simple, stylized version of a plot
of data that would be obtained from performing such an analysis is
shown as FIG. 6.
[0236] More specifically, FIG. 6 provides a simplified
2-dimensional representation of a large conventional gas field. A
permeable sandstone reservoir rock has undergone deformation so as
to have a structure suitable for trapping oil #1. The sandstone
reservoir #1 is overlain by a shale having low permeability #2 that
acts as a seal. Gas has migrated into the sandstone reservoir #1
from a deeper source and now fills the sandstone down to the gas
water contact (GWC) #3. The sandstone shallower than the GWC is
charged with gas. The pores in the sandstone, which are deeper than
the GWC, are filled with water. Formic and acetic acids occur in
oils and wet gases, and can partition out of the gas and oil phase
into the water phase. These light carboxylic acids are miscible in
water. An aspect of the invention is the realization that
measurement of high amounts of these acids in formation waters in
water-filled permeable reservoir formations indicates close
proximity to large economic pay zones in conventional oil and gas
plays #6. In unconventional reservoirs with very limited
permeability the oil and gas coexist in intimate contact with high
amounts of formation water, and often in those cases the proximity
to pay indicating acids occur in high amounts within the pay zone
itself. This is the case in the previous Examples. However, in this
conventional high permeability example, the gas and water are able
to segregate into separate distinct zones as controlled by gravity
separation.
Example 7
[0237] This Example provides the results of analysis performed with
wet reservoir sands directly beneath two small local oil pay zones,
as well as two wet sand that are down dip from a giant gas
reservoir, as shown in FIG. 7. The resistivity log indicates two
small uneconomic pay zones in this well, #2 and #3. Five
rectangular boxes, #4a-#4e, are the sandstone bodies in this well
as indicated by the gamma ray log. The rest of the penetrated
strata depicted here are shales. Sands #4a and #4e have small oil
legs at the top of the sands, and are water wet below the oil.
Sands #4c and #4d are water wet, but are continuous with reservoir
sands to a giant gas field up dip. Sand #4b is water wet and has no
updip pay. The acetic acid information is plotted against a
resistivity log. This data provides not only information about the
presence of oil pay zones, but mapped against the nature of the
material also reflects where in the site would provide the best
economic payout.
[0238] It can be advantageous to relate the methods and results of
this Example to the disclosures in Example 6 and FIG. 6, in that
the material of this Example contains a thick water charged
sandstone having row resistivity and being located about one half
mile laterally and 500 feet in depth down dip to a large gas field
#1 that produces from the same sandstone formation. There are no
seals between the gas field and this dry hole. The sandstone, which
is the source/cause of the dry hole, is in good permeable
communication to the same sandstone formation in the giant gas
accumulation, as shown in FIG. 6.
[0239] Although this sand in fully water charged and shows low
resistivity at this location, the entire sandstone body shows high
acetic acid contents, which, according to an aspect of the
invention, is indicative of proximity to the giant nearby gas field
#1 in FIG. 7. If this well was drilled prior to the nearby giant
field being discovered, the conventional logs and other types of
conventional analyses that might have previously ordinarily be
applied to these samples, would have provided no indications that
this well is in close proximity to the giant gas field. However,
the high acetic acid anomalies #1 in these wet sands #4c and #4d,
provide a unique indication of the existence of a large nearby
petroleum accumulation. These data would strongly support further
exploration in this area.
[0240] There is another sand in FIG. 7 that is water wet and
contains no pay #4b. The acetic acid contents of sand 4b are
similar to the surrounding shales above and below it. From other
wells drilled in this area it was known that sand 4b is not charged
with gas or oil updip to this location. The low acetic acid
contents of sand #4b relative to the obviously higher acetic acid
concentrations in zones #4c and #4d provides a local calibration
that indicates the importance of the acetic acid in sands #4c and
#4d with respect to analyzing the characteristics of the
material/formation.
[0241] There are two more sands #4a and #4e that the resistivity
log indicates have small pay zones at the top of each sand. In each
of these sands with minor pay zones #4a and #4e, acetic acid
anomalies #5a for sand #4a and #6a for sand #4e can be seen. A very
interesting aspect of acetic acid anomalies #5a and #6a is that
they also only occur near the top of each sand. The acetic acid
anomaly for sand #4c and #4d is high for the entire sand body. This
is the situation that was expected for a sand such as depicted in
FIG. 6, wherein the entire sand body is charged with oil or gas
updip. Diffusion and fluid flow in geologic formations is usually
much easier along bedding than across bedding. Hence the fact that
the entire sands #4c and #4d show high acetic acid contents is an
indication that those sands are completely charged at some distance
updip, and they are. On the other hand, the fact that sands #4a and
#4e show acetic acid anomalies only at the top of the sands is an
indication that this is a small oil deposit of only local extent
and may be of lower or even insufficient economic interest with
respect to drilling. The acetic acid is observed only directly
adjacent to the small oil columns seen in the resistivity log as
#5a and #6a. Most of each #4a and #4e sand lacks any acetic acid
anomaly as shown by the lower portions of each sand as #5b and
#6b.
[0242] This data reflects that an aspect of the invention is the
use of acetic acid data derived from geologic formations to
classify the analyzed sands. Sand #4b shows no increase in acetic
acid relative to the shales immediately above and below, and
therefore sand #4b was determined to be non-prospective, and data
from surrounding wells support that interpretation. There are only
very localized acetic acid anomalies at the top of sands #4a and
#4e, and this data indicates these acetic acid anomalies #5a and
#6a are local in nature and not indicative of nearby economically
significant pay. On the other hand, the entirety of sand #4c and
#4d show high acetic acid contents. Even though the magnitude of
the anomaly in sand #4a is higher than that in sands #4c and #4d,
the fact that the anomalies in #4c and #4d encompass the entire
sand, whereas the anomalies in sands #4a and #4e encompass only the
top of the sands is indicative that the #4c and #4d anomalies are
related to/indicative of large and likely economically significant
pay zones, in contrast to the implications derived from the more
limited anomalies in sand #4a and #4e. Thus, this Example
demonstrates how the inventive methods of the invention can be used
to "map" or characterize an entire geologic structure or region
with respect to proximity to petroleum pay zones in the
structure/region.
Example 8
[0243] Plots were obtained from the performance of methods
described above for a "dry gas" site and a "wet gas" site. The
results of these analyses are shown in FIGS. 8A and 8B. A stylized
interpretation of this data is shown in FIG. 8C. This analysis
reflects the ability of methods of the invention to distinguish
between the nature of various target sites.
[0244] In FIG. 8a, a dry gas anomaly deep in the well is dominated
by methane #1, ethane #2, and propane #3. Higher liquid
hydrocarbons are essentially absent, with the exception of a trace
amount of benzene #4 that can be barely seen. The curve #5 shows
the total amount of ethane that would be produced from a standard
lateral drilled about 4,500 feet long with a production radius of
about 50 feet. The analyst can calculate this number as the number
of nanomoles of the gases to be analyzed can be determined as the
results are quantitative and referenced to analytical standards,
and the volume of sample analyzed is kept constant to 400
microliters of rock for each sample. The result shown as curve #5
is simply the result of upscaling the data to how much ethane by
volume the analytical results are equivalent to for a cylindrical
rock volume that is 4,500 ft long with a radius of 50 ft.
[0245] FIG. #8B is plotted at the same scale as FIG. #8A. As shown,
there is much less methane #1, ethane #2, and propane #3 here.
Also, the data reflects there is much more liquid hydrocarbon
content than seen in the data of FIG. 8A. The C4-C8 paraffins are
shown as #4-#8, the C6 to C8 naphthenes are shown as #9-#11, and
the C6-C8 aromatics are shown as #12-#14. The track showing
predicted ethane production #15 is insignificant compared to the
same track #5 in FIG. 8A plotted at the same scale. However, the
predicted liquids production is much higher in FIG. 8B than in FIG.
8A. FIGS. 8A and 8B both depict unconventional wells where the
source rock is also the reservoir after hydraulic fracking. The
source rock in the well shown in FIG. 8A has been buried to much
greater depths and thus has generated much drier gas than the
source rock in the well shown in FIG. 8B. The gas compositions
derived from these analyses thus provide information about burial
history of the target formations, which is a critical piece of
information in petroleum exploration, both for conventional and
unconventional reserves.
[0246] This situation is shown in the simplified diagrams on FIG.
8C. The drier gas shown as #1 is produced from the source rock that
has experienced much higher temperatures for much longer periods of
time then the wetter gas shown as #2.
[0247] These data can be used to address a great variety of
geologic issues, especially when combined with other information
from a variety of sources.
[0248] Analysis can be and often will be applied to relatively
greater sized hydrocarbons, such as up to C10 hydrocarbons, but the
C9 and C10 data obtained in this work were omitted from the FIGS.
8a and 8b for the sake of clarity. Since FIGS. 8A and 8B are
plotted at the same scales, it is apparent that the gas from the
FIG. 8A well is much drier than the gas from the FIG. 8B well. This
Example reflects several aspects of the invention--from making
standards to using such standards or more generally comparing data
from several well sites to characterize a multi-well
geographic/geological area.
Example 9
[0249] Methods of the invention could be applied to map out
regions, as noted elsewhere herein. An illustration of the concept
is shown as FIG. 9. FIG. 9 provides an example of what the output
of such a regional mapping of oil well sites would conceptually
look like, providing areas of high oil indications #1 and/or other
information, such as porosity, which could be used to provide maps
of favorable drilling sites and also used to predict other less
prospective sites versus zones of low oil indications #2 or zones
of low proximity to pay indications, or other indications from the
data that can attest to high or low probability of finding oil
and/or gas.
Example 10
[0250] In this Example, data was gathered in a manner similar to
the protocols described in Examples 2-4. The data obtained from
this analysis is shown as FIG. 10 and an interpretation of the data
is provided as FIG. 10A.
[0251] The well depicted in FIG. 10 was drilled for a deeper target
and there was no effort expended in searching for pay zones in the
shallower part of the well depicted in FIG. 10. However, analyses
of samples shown in FIG. 10 revealed a 600-foot oil column that was
indicated by high oil saturated water #1 and high formic and acetic
acids #2. As discussed above, in unconventional reservoirs having
very low permeability, one or more proximity to pay indicators,
e.g., formic and acetic acids, can delineate the pay zone in as
much as the water and oil coexist in the same strata in an
unconventional reservoir, and do not separate out into discrete oil
pay zones versus water legs as happens in much more permeable
conventional reservoir settings.
[0252] The 600-foot oil column detected by oil saturated water #1
and organic acids #2 is actually two oil accumulations that are
juxtaposed one on top of the other. Analysis of the data allows for
discrimination of these two oils as having different chemical
compositions using the paraffins/(paraffins+naphthenes) and the
aromatics/(aromatics+naphthenes) curves #3, with relatively low
values for both these ratios in the upper 400 feet of the pay zone
#3 that was identified defined using oil saturated water #1, and
organic acids #2. However, data #4 shows high values for both of
these ratios for the deepest 200 feet of this pay zone. The data
indicate to those skilled in the art that the oil in upper zone #3
is heavier than the oil in the lower zone #4. This is somewhat
unusual if this were a conventional oil and gas reservoir system,
as in those systems oil and gas become stratified by gravity
according to density, that is to say in conventional reservoirs
petroleum is usually stratified with the lighter petroleum above
the heavier petroleum. This, however, is not a trend that has
particular relevance in unconventional reservoirs with vanishingly
small permeabilities. In this case, the data obtained by the
inventive method indicates that the #3 reservoir is a tight
carbonate into which oil and gas have migrated into from some
source rock that is spatially removed from the reservoir. Reservoir
#4 in contrast is an organic-rich shale that is both the source for
the oil it holds, and the reservoir for the oil. Unconventional oil
from source rocks tends to be lighter than migrated oil. Migrated
oil tends to lose lighter hydrocarbons during expulsion from the
source rock, i.e., primary migration, and transport to the
reservoir, i.e., secondary migration, and during the residence of
the petroleum in the reservoir. As tight shales can be both source
and reservoir, the oil in tight shales does not lose its more
volatile components during migration and while being in the
reservoir, and hence is usually lighter than conventional oil.
Hence it is reasonable to conclude that the overlying oil #3 in a
tight limestone is heavier than the underlying oil in a tight
organic-rich shale.
[0253] From a production point of view reservoir #3 and reservoir
#4 will need to be produced as separate reservoirs. Reservoirs #3
and #4 are not in communication. They will produce different types
of oil. And various aspects of the reservoir, such as fluid
pressure, will be different. This reflects an advantageous element
of the invention in identifying and characterizing separated pay
zones of separate characteristics.
[0254] FIG. 10A illustrates other aspects of this Example. Curve #1
on the left is the resistivity curve that indicates a 600-foot oil
column overlain and underlain by water, as shown by the product
type log #2. The 600-foot oil column #1 is shown to be divided into
a 400-foot-thick upper heavier oil reservoir and a deeper
200-foot-thick lighter oil reservoir #4. The distinction between
shallow heavy oil reservoir #3 and deeper lighter oil reservoir #4
is based on the paraffins/naphthenes ratio curve #5 and the
aromatics/naphthenes ratio curve #6.
[0255] The results of this analysis demonstrate that methods of the
invention as exemplified here can identify two separate oil pay
zones, and further demonstrate that the cutting analysis methods of
the invention can be used to distinguish between different types of
oil pay zones in a well site, which might otherwise be confused
with one another based on other methods of analysis.
Example 11
[0256] Methods of the invention can be performed to demonstrate
different oil pay zones at a site due to the presence of different
profiles of hydrocarbons present in the respective sites. In this
respect, the methods of the invention could be used to identify
compartmentalized and discrete oil pay zone sites. A reflection of
this concept is provided in FIG. 11.
[0257] As shown in FIG. 11, Well A #1 and Well B #2 are both oil
wells drilled in similar geologic situations. The oil pay zone in
Well A #3 is oil comprised of high paraffins and aromatics content,
but low naphthenes content. The oil pay zone in Well B #4 contains
oil comprised of high paraffins and aromatics content, but also
high naphthenes content. The oil in reservoir #3 will have a
different character from the oil in reservoir #4. Documenting the
difference using data obtained by the inventive methods described
herein will then allow those trained in the art of oil exploration
to consider various scenarios to account for this observed
difference. Also, the knowledge that two different oils occurring
in one area reduces exploration risk in that area as the
probability of finding oil is increased if there is more than one
oil source that can charge reservoirs in the area being
explored.
Example 12
[0258] This Example provides an illustration of a method for the
measurement of many of the above-described parameters associated
with a sample for characterizing a material in a well site device
according to certain aspects of the invention, where the inventive
method involving the use of the device occurs while the well is
drilling at such a rate so that the data are obtained as quickly as
possible so that those data can be used to help "steer" the well in
a close to "real time" manner (it is expected that there may often
be a "lag" of about 10-100, such as about 20-60 feet, from the
location of the active drill and the latest location of data
analysis, simply given the logistics of well operations, such as
limitations of what can be placed at a drill bit, interfering noise
and motion, etc.). Aspects of the invention such as the device and
method envisioned here can be advantageous for the optimum
placement of lateral wells, also known as horizontal wells.
[0259] A device for a rapid method for determining frackability on
the well site is depicted in FIG. 12. With reference to the device
of FIG. 12, #1 depicts the discharge of mud and cuttings from the
flow line and into the possum belly of a conventional oil well. A
reusable collapsible container, #2, is positioned so that a portion
of the mud and cuttings discharge must flow through it. A screen,
#4, is placed at the bottom of reusable collapsible container, #2,
that allows drilling mud to escape the reusable collapsible
container #2, but retains the cuttings #3 inside the container. An
air piston, #5, is situated outside of the mud and cuttings
discharge #1. The air piston #5 transmits unidirectional force for
crushing the cuttings #3 through the elongate rod #6. A rotating
device, #7, usually driven by air pressure rotates the screen #4
using rod #8 away from the collapsible container #2 to discharge
material from the cuttings #3 after they have been crushed. The
screen #4 is retracted from the reusable collapsible container #2
for a sufficient amount of time to allow the now crushed cuttings
#3 to be removed from the reusable collapsible chamber #2 to be
cleansed from the chamber by the vigorous flow of mud and cuttings
#1. The device #7 could be another air piston that moves the screen
laterally out from under reusable collapsible container #2 instead
of a rotating device.
[0260] The top view shows the reusable collapsible container #2 is
comprised of two parts. Part #9 is U-shaped in cross section having
two right angle corners. The fourth wall of the reusable
collapsible container is a plate #10 that has no solid connection
with part #9 of the container. Upon filling of the reusable
collapsible container #9 and #2 with cuttings #3 from the flow line
mud and cuttings discharge #1, the cuttings are crushed by
activating air piston #1 to squeeze them through transmitting a
force through rod #11 to the plate #10. The frackability of the
cuttings is determined by measuring and recording how much the rod
#11 has been extended out from the air piston #12. The speed and
fluidity of motion of the crushing of the cuttings #3 can also be
recorded, as can any recovery of the crushing assembly upon release
of force on air piston #12. These parameters can aid in a more
complete description of the mechanical properties of the cuttings,
including Poisson's Ratio, and Young's modulus. These parameters,
along with frackability, can be important and useful in steering a
lateral to stay in the rocks of optimum mechanical strength, and in
determining the best manner in which to complete the lateral
through the fracking and production stages of oil production.
LIST OF ILLUSTRATIVE ASPECTS OF THE INVENTION
[0261] The following is a non-limiting list of certain aspects of
the invention that can provide additional assistance and guidance
in understanding the unique features and advantages that the
invention provides.
[0262] The first set of aspects relates to methods in which
multiple aliquots are obtained from a sample and the volatile
substances in such aliquots analyzed: [0263] 1. A method for
analyzing volatile substances in a material comprising: [0264] a.
Providing an analyzable sample of a material [0265] b. Subjecting
the sample to one or more forces to release a first gas containing
an analyzable amount of one or more volatile substances, [0266] c.
Trapping and concentrating the first gas in or with a media in an
analyzable amount to generate an aliquot, [0267] d. Isolating the
aliquot from the sample, [0268] e. Releasing volatile substances
from the aliquot as released gasses in a predictable sequence,
[0269] f. Analyzing the volatile substance chemistry of at least
one of the volatile substances to obtain an analysis of the
aliquot, [0270] g. Performing at least one more cycle of analysis
comprising repeating steps b-f of the method, at least one
additional time, wherein for each repetition the specific force
applied is distinct from the force previously applied to the
sample, and [0271] h. Analyzing all of the analyses to provide
information about the material. [0272] 2. The method of aspect 1,
wherein the one or more forces comprises subjecting the sample to a
specific pressure without mechanical disruption, e.g., crushing.
[0273] 3. The method of aspect 2, wherein the sample is initially
subjected to the specific pressure at which it was sealed in its
container so as no unsealed volatiles are lost. This is usually
performed at about 1-100 millibars, such 2-80 millibars, e.g.,
about 3-75 millibars. [0274] 4. The method of any one of aspects
1-3, wherein the sample is subjected to the specific pressure and
temperature at which it was initially obtained. [0275] 5. The
method of any one of aspect 4, wherein the method comprises
subjecting the sample to different pressures, without mechanical
disruption. [0276] 6. The method of any one of aspects 1-5, wherein
the analysis of the volatile substance chemistry comprises
subjecting the volatile substances to mass spectrometry. [0277] 7.
The method of any one of aspects 1-6, wherein the analysis provides
information concerning the quantity of one or more volatile
compounds in the material. [0278] 8. The method of any one of
aspects 1-7, wherein step h of the method (the analysis step)
comprises comparing at least some of the analyses against one or
more standards. [0279] 9. The method of any one of aspects 1-8,
wherein the force comprises dehydrating the sample prior to
crushing, applying mechanical pressure on the sample, mechanically
rupturing some or all of the sample, subjecting the sample to a
chemical reaction, or a combination of any thereof. [0280] 10. The
method of any one of aspects 1-9, wherein the method further
comprises subjecting the sample to two or more different pressures,
optionally to generate two or more aliquots. [0281] 11. The method
of any one of aspects 1-10, wherein the volatile substances
comprise C1-C20 hydrocarbons. [0282] 12. The method of any one of
aspects 1-11, wherein the step of trapping comprises subjecting the
gas to a non-selective trap. [0283] 13. The method of any one of
aspects 1-12, wherein the step of trapping comprises cryogenic
capture of the gas. [0284] 14. The method of aspect 13, wherein the
trapping step comprises subjecting the gas to temperatures of less
than about -50 degrees C. [0285] 15. The method of aspect 14,
wherein the method comprises contacting the gas to a material
cooled by contact with liquid nitrogen. [0286] 16. The method of
any one of aspects 1-15, wherein the volatile substances comprise
C1-C10 hydrocarbons. [0287] 17. The method of any one of aspects
3-16, wherein the pressure is either ambient atmospheric pressure
positive pressure in excess of ambient atmospheric pressure, or a
level of vacuum below atmospheric pressure but greater than
3.times.10.sup.-4 millibars. [0288] 18. The method of aspect 17,
wherein the pressures applied to the sample are greater than
1.times.10.sup.-3 millibars. [0289] 19. The method of aspect 18,
wherein the pressures applied to the sample are greater than
25.times.10.sup.-3 millibars. [0290] 20. The method of aspect 19,
wherein the pressures applied to the sample are greater than
1.times.10.sup.-2 millibars. [0291] 21. The method of any one of
aspects 3-20, wherein the method comprises subjecting the sample to
a pressure of between 1-100 millibars. [0292] 22. The method of any
one of aspects 1-21, wherein the sample is a rock that comprises no
recent fluid inclusions that could have trapped recent fluids such
as present day oil and/or gas. [0293] 23. The method of aspect 22,
wherein the sample has not experienced significant burial
diagenesis. [0294] 24. The method of any one of aspects 1-23,
wherein the method comprises removing potentially interfering
gasses from contact with the media prior to analyzing gasses
released from the aliquot. [0295] 25. The method of aspect 24,
wherein the interfering gasses removed comprise oxygen, nitrogen,
or both oxygen and nitrogen. [0296] 26. The method of aspect 25,
wherein the method comprises purging oxygen and nitrogen from
contact with the media by contact with an inert gas that does not
chemically react with the sample and does not cause any
interferences with the chemical analyses of the samples' volatiles.
[0297] 27. The method of aspect 26, wherein the inert gas is an
inert gas, such as argon or nitrogen. [0298] 28. The method of any
one of aspects 1-27, wherein more than 50% of the volatile
substances in the sample are analyzed by the method. [0299] 29. The
method of aspect 28, wherein more than 75% of the volatile
substances in the sample are analyzed by the method. [0300] 30. The
method of aspect 30, wherein more than 90% of the volatile
substances in the sample are analyzed by the method. [0301] 31. The
method of aspect 30, wherein more than 99% of the volatile
substances in the sample are analyzed. [0302] 32. The method of any
one of aspects 1-31, wherein the first gas is allowed to contact
the media for 0.1 seconds to 10 minutes. [0303] 33. The method of
any one of aspects 1-32, wherein the first gas is allowed to
contact the media for about 10 minutes or longer. [0304] 34. The
method of aspect 33, wherein the first gas is allowed to contact
the media for about 20 minutes or longer. [0305] 35. The method of
aspect 34, wherein the first gas is allowed to contact the media
for about 40 minutes or longer. [0306] 36. The method of any one of
aspects 1-35, wherein the method does not comprise heating the
sample to temperatures greater than 100.degree. C. [0307] 37. The
method of aspect 36, wherein the method does not comprise heating
the sample to temperatures greater than 60.degree. C. [0308] 38.
The method of any one of aspects 1-37, wherein the method comprises
collecting a portion of the first gas of at least one of the cycles
that will not bind to the media as a separate non-condensable gas
and subjecting this non-condensable gas aliquot to a separate
analysis. [0309] 39. The method of aspect 38, wherein the media is
a cooled surface to which the first gas condenses and at least some
of the portion will not condense on the cooled surface. [0310] 40.
The method of aspect 38 or aspect 39, wherein the method comprises
isolating the non-condensable gas from the condensable gasses to
facilitate separate analysis thereof. [0311] 41. The method of any
one of aspects 38-40, wherein the portion of the non-condensable
gas comprises methane, helium, hydrogen, or a combination of some
or all thereof. [0312] 42. The method of any one of aspects 38-41,
wherein the portion of the non-condensable gas comprise neon,
argon, krypton, or a combination of two or more of these gasses.
[0313] 43. The method of any one of aspects 1-42, wherein the
method comprises containing the sample in a container which
isolates the sample from the environment in a manner that
substantially retains volatile substances in the sample from the
time the sample is placed in the container until release of the
first gas. [0314] 44. The method of aspect 43, wherein the
container comprises a seal that can be selectively punctured to
release the first gas allowing gaseous contents of the container to
flow into contact with the media when punctured. [0315] 45. The
method of aspect 43, wherein the container comprises a
puncture-free connector system. [0316] 46. The method of any one of
aspects 1-45, wherein the method comprises collecting the first gas
under each different condition for at least about 1 minute to form
each aliquot. [0317] 47. The method of any one of aspects 1-46,
wherein the method comprises the step of substantially removing one
or more potentially interfering gasses before trapping the first
gas. [0318] 48. The method of aspect 47, wherein the step of
removing potentially interfering gasses is completed in about 3
seconds or less. [0319] 49. The method of aspect 47 or aspect 48,
wherein the potentially interfering gasses comprise oxygen,
nitrogen, carbon dioxide, or a combination thereof. [0320] 50. The
method of aspect 47 or aspect 49, wherein the method comprises
purging the potentially interfering gas from contact with the media
by filling the area surrounding the media with a purging gas, such
as a non-condensable gas. [0321] 51. The method of aspect 50,
wherein the purging gas is argon or krypton. [0322] 52. The method
of any one of aspects 1-51, wherein the media is a cooled surface.
[0323] 53. The method of aspect 52, wherein the surface is cooled
by indirect contact with liquid nitrogen, or another cryogenic
liquid such as liquid argon, liquid oxygen, or liquid helium.
[0324] 54. The method of any one of aspects 1-53, wherein the
method comprises performing an optional analysis at atmospheric
pressure and at least two analyses at different pressures both of
which are below atmospheric pressure. [0325] 55. The method of any
one of aspects 1-54, wherein the method does not comprise
performing gas chromatographic analysis. [0326] 56. The method of
any one of aspects 1-55, wherein the method comprises evaluating
the permeability of the sample by assessing differences in the
aliquots obtained by extraction under two different sets of
conditions.
[0327] The following listing of aspects of the invention is
directed to a method of the invention comprising extracting and
analyzing only a single aliquot of material: [0328] 57. A method
for analyzing volatile substances in a material comprising: [0329]
a. Providing an analyzable sample of a material [0330] b.
Subjecting the sample to one or more forces to release a first gas
containing an analyzable amount of one or more volatile substances,
[0331] c. Trapping and concentrating the first trappable gas (such
as a condensable gas in a system that relies on condensation of the
gas) in or with a media in an analyzable amount to generate an
aliquot, [0332] d. Isolating the aliquot from the sample, [0333] e.
Releasing volatile substances from the aliquot as released gasses
in a predictable sequence, and [0334] f. Analyzing the volatile
substance chemistry of at least one of the volatile substances to
obtain an analysis of the aliquot. [0335] 58. The method of aspect
57, wherein the method comprises only forming and analyzing a
single aliquot, which may comprise two or more sub-aliquots. [0336]
59. The method of aspect 58, wherein the single aliquot comprises a
condensable gas component that is trapped with a first trap and a
non-condensable gas component that is separately collected. [0337]
60. The method of any one of aspects 57-59, wherein the method
comprises subjecting the sample to at least one pressure of at
least 1 millibar and less than 1 atmosphere. [0338] 61. The method
of aspect 60, wherein the method comprises subjecting the sample to
a pressure of about 1 millibar to about 100 millibars. [0339] 62.
The method of any one of aspects 57-61, wherein the sample is
subjected to vacuum pressure for a period of about 0.25 minutes to
about 15 minutes. [0340] 63. The method of any of aspects 57-62,
wherein the one or more forces comprises subjecting the sample to a
crushing force in addition to one or more other forces such as
vacuum pressure, vibrational energy, or radiation energy, such as
laser excitation, or a combination of any or all thereof. [0341]
64. The method of any one of aspects 57-63, wherein the analysis of
the volatile substance chemistry comprises subjecting the volatile
substances to mass spectrometry or other method of analysis. [0342]
65. The method of any one of aspects 57-63, wherein the step of
trapping comprises cryogenic capture of condensable gas and
optionally capturing a sub-aliquot of non-condensable gas in a
separate manner for separate analysis. [0343] 66. The method of any
one of aspects 57-65, wherein the method comprises removing
potentially interfering gasses from contact with the media prior to
analyzing gasses released from the aliquot. [0344] 67. The method
of any one of aspects 57-66, wherein the method does not comprise
heating the sample to temperatures greater than 100.degree. C.
[0345] 68. The method of any one of aspects 57-67, wherein the
method comprises measuring the ductility of the sample by providing
the sample in a crushable container and determining the size of the
impact of the crushing force on the container and sample. [0346]
69. The method of any one of aspects 57-68, wherein the method
comprises collecting and sealing samples at the wells versus loaded
in lab samples. [0347] 70. The method of any one of aspects 57-69,
wherein the method comprises collecting and analyzing samples in
close proximity to the well site. [0348] 71. The method of any one
of aspects 57-70, wherein the method comprises collecting and
analyzing samples inside a well, such as a well that is under
active drilling. [0349] 72. The method of aspect 71, wherein the
method comprises real-time or near real-time analysis of samples,
for example where the lag time between the site of drilling and the
analysis of samples is less than about 50 feet, such as less than
about 40 feet, less than about 30 feet, less than about 20 feet, or
less than about 10 feet, 7 feet, 5 feet, or even less than about 1
foot. [0350] 73. The method of any one of aspects 57-72, wherein
the method comprises measuring the amount of acetic acid, formic
acid, and/or oil saturated water associated with the sample. [0351]
74. The method of any one of aspects 57-73, wherein the method
comprises measuring the amount of methane, carbon dioxide, and/or
carbon monoxide that is released from the trap. [0352] 75. The
method aspect 74, wherein the method comprises measuring the amount
of carbon monoxide that is released from the trap. [0353] 76. The
method of any one of aspects 57-75, wherein one or more steps of
the method are performed in close proximity to a petroleum well
site. [0354] 77. The method of aspect 76, wherein the method is
performed within about 150 feet of the site of drilling. [0355] 78.
The method of aspect 77, wherein the method comprises pneumatic
delivery of samples to a laboratory for analysis. [0356] 79. The
method of aspect 78, wherein the method comprises analysis in
real-time while the well is drilling and the data is used to steer
the well to keep the borehole in or as close as possible to the
target pay zone.
[0357] In general, the aspects that are dependent on aspect 57 can
apply to the method of aspect 1. The aspects that are dependent on
aspect 1 can be applied to aspect 57. In fact, aspect 1 can be
considered to depend from aspect 57. Any of these methods reflected
in aspects 1-79 can comprise developing a standard and/or adjusting
for conditions at a location (e.g., calculating carbon monoxide
located at a location and substracting it from a measured amount,
or applying a similar approach to formic acid, acetic acid, and/or
oil saturated water).
[0358] The following set of aspects is directed to a method focused
on primarily assessing ductility (frackability) of a material by
performance of a method of the invention: [0359] 80. A method for
analyzing the ductility or hardness of geologic formation
comprising: [0360] a. Providing an analyzable sample of a material,
[0361] b. Subjecting the sample to one or more forces that are
capable of compressing material of a given hardness or ductility,
and [0362] c. Determining the amount of compression of the sample.
[0363] 81. The method aspect 80, wherein the method comprises
compressing multiple sides of the sample contemporaneously. [0364]
82. The method of aspect 81, wherein the method comprises
isotopically compressing the sample. [0365] 83. The method of any
one of aspects 80-82, wherein the sample is obtained from a
petroleum well. [0366] 84. The method of aspect 83, wherein the
sample is selected from a cutting and a core sample. [0367] 85. The
method of aspect 84, wherein the sample is a cutting. [0368] 86.
The method of any one of aspects 80-85, wherein the method is
performed on multiple samples from a site. [0369] 87. The method of
aspect 86, wherein the samples comprise samples obtained from
different depths of a material wherein the depths range from about
0.5 feet to about 100 feet. [0370] 88. The method of aspect 86 or
aspect 87, wherein the samples comprise materials obtained from the
same approximately the same zone of depth but from locations that
are separated by about 0.5 feet to 100 feet. [0371] 89. The method
of any one of aspects 86-88, wherein the method comprises analyzing
at least 10 samples from different depths. [0372] 90. The method of
any one of aspects 86-89, wherein the method comprises analyzing at
least 10 samples from the same zone of depth. [0373] 91. The method
of any one of aspects 86-90, wherein the method comprises analyzing
about 10 to about 2,500 samples. [0374] 92. The method of any one
of aspects 80-91, wherein the method comprises combining the
results of the method with the results of mineralogic analysis of
the sample, other samples, or the material, x-ray diffraction of
the samples, other samples or the material; x-ray fluorescence of
the samples, other samples, or the material; a total organic
content measurement associated with the samples, other samples, or
the material, and/or combination with other data such as
photography and/or spectroscopy of the samples or other samples or
the material by any suitable means in any wavelength, and/or
chemical, geochemical, or material testing of the samples, related
samples, or the material, or a combination of any or all
thereof.
[0375] The following set of aspects are directed to a device of the
invention for the analysis of oil saturation and/or water
saturation from samples: [0376] 93. A device comprising: [0377] (a)
a chamber for receiving and isolating samples of a material [0378]
(b) a detection component capable of detecting the amount of one or
more target volatile substances released from the sample, wherein
the substance comprises carbon monoxide, acetic acid, formic acid,
or a combination thereof, optionally in combination with
hydrocarbons, inorganic gasses, or a combination thereof. [0379]
94. The device of aspect 93, wherein the device comprises an energy
input component that promotes the release of volatile substances
from the sample. [0380] 95. The device of aspect 94, wherein the
energy input component is (a) a pressure generating device or
system, (b) a device or system that promotes release of volatile
substances through mechanical forces, thermal forces, or both, or a
combination of (a) and (b). [0381] 96. The device of any one of
aspects 93-95, wherein the device comprises a system or component
for isolating volatile substances released from the sample. [0382]
97. The device of any one of aspects 93-96, wherein the device
comprises a trap for collection and release of volatile substances.
[0383] 98. The device of aspect 97, wherein the trap comprises a
non-selective trap, such as a trap that comprises a liquid nitrogen
trap. [0384] 99. The device of any one of aspects 93-98, wherein
the device comprises a mass spectrometer. [0385] 100. The device of
any one of aspects 93-99, wherein the device comprises a component
or device for selectively isolating the mass spectrometer from the
sample. [0386] 101. The device of aspect 100, wherein the device
comprises a volatile substance trap and the method comprises a
component or device for selectively isolating the volatile
substance trap from the sample, the mass spectrometer, or both.
[0387] 102. The device of any one of aspects 93-101, wherein the
device is part of a system that comprises a mechanism for
determining the compressibility of the sample.
[0388] The following set of aspects are directed to another type of
device provided by the invention: [0389] 103. A device for chemical
analysis comprising: (a) a cryogenic trap, (b) a cooling component
for selectively cooling the cryogenic trap, (c) a warming component
for selectively warming the cryogenic trap, and (d) an analytical
device comprising a mass spectrometer for analyzing one or more
volatile substance released from the cryogenic trap. [0390] 104.
The device of aspect 103, wherein the warming component is operable
in a manner that provides for controlled warming of the cryogenic
trap to promote separate release of two or more amounts of volatile
substances from the cryogenic trap. [0391] 105. The device of
aspect 103 or aspect 104, wherein the device further comprises a
vacuum that can promote the release of volatile substances from a
material in communication with the device, wherein at least one of
the volatile substances can be trapped on the trap. [0392] 106. The
device of any one of aspects 103-105, wherein the device comprises
one or more housing components that keep at least an analyzable
proportion of the volatile substances captured by the trap separate
from the environment. [0393] 107. The device of any one of aspects
103-106, wherein the device further comprises a component for
promoting the flow of substances through the device, such as one or
more selectively operable pumps. [0394] 108. The device of any one
of aspects 103-107, wherein the device comprises a component or
system for capturing one or more substances that do not bind to the
cryogenic trap and for separately analyzing such one or more
non-binding substances. [0395] 109. The device of any one of
aspects 103-108, wherein the device comprises components for
delivering a cryogenic substance selected from the group consisting
of liquid nitrogen, liquid argon, liquid oxygen, liquid air, liquid
helium, dry ice, a dry ice slurry, normal ice, a normal ice slurry
of water ice in fresh water, a normal ice slurry of water ice in a
saline brine, or any other naturally cooling substance capable of
achieving the minimum temperature required to freeze the
substance(s) of interest onto the cryogenic trap. [0396] 110. The
device of any one of aspects 103-109, where the cryogenic state of
the trap is at least partially achieved, and the device comprises
components for mechanical refrigeration or cooling, as may be
achieved with, e.g., a Kelvinator device. The Kelvinator or other
cryogenic device must be able to achieve the minimum temperature
required to freeze the substance(s) of interest onto the cryogenic
trap. [0397] 111. The device of any one of aspects 103-110, where
the device further comprises an additional mass spectrometer, a gas
chromatograph; an infrared spectrometer; a Raman spectrometer; or
any combination of these analytical devices.
[0398] In another aspect of the invention, the methods, systems,
and devices described above further comprise components for or
steps for determining the permeability of a sample, through
application of two different forces, such as two different
pressures, to each sample analyzed for permeability, and analyzing
the difference in the release of one or more substances or
substance classes, such as hexanes, upon the application of the
different forces. Any one of the above described 102 aspects can be
further modified by addition of such step or the inclusion of
settings or components for practicing such steps.
INCORPORATION BY REFERENCE AND INTERPRETATION
[0399] All references, including publications, patent applications,
and patents, cited herein are hereby incorporated by reference to
the same extent as if each reference were individually and
specifically indicated to be incorporated by reference and were set
forth in its entirety herein.
[0400] The use of the terms "a" and "an" and "the" and similar
referents in the context of describing the invention (especially in
the context of the following claims) are to be construed to cover
both the singular and the plural, unless otherwise indicated herein
or clearly contradicted by context. The terms "comprising,"
"having," "including," and "containing" are to be construed as
open-ended terms (i.e., meaning "including, but not limited to,")
unless otherwise noted. Recitation of ranges of values herein are
merely intended to serve as a shorthand method of referring
individually to each separate value falling within the range,
unless otherwise indicated herein, and each separate value is
incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
claimed. No language in the specification should be construed as
indicating any non-claimed element as essential to the practice of
the invention.
[0401] Preferred embodiments of this invention are described
herein, including the best mode known to the inventors for carrying
out the invention. Variations of those preferred embodiments may
become apparent to those of ordinary skill in the art upon reading
the foregoing description. The inventors expect skilled artisans to
employ such variations as appropriate, and the inventors intend for
the invention to be practiced otherwise than as specifically
described herein. Accordingly, this invention includes all
modifications and equivalents of the subject matter recited in the
claims appended hereto as permitted by applicable law. Moreover,
any combination of the above-described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *